/* |
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* Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.lang; |
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import java.io.ObjectStreamField; |
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import java.io.UnsupportedEncodingException; |
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import java.nio.charset.Charset; |
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import java.util.ArrayList; |
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import java.util.Arrays; |
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import java.util.Comparator; |
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import java.util.Formatter; |
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import java.util.Locale; |
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import java.util.Objects; |
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import java.util.StringJoiner; |
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import java.util.regex.Matcher; |
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import java.util.regex.Pattern; |
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import java.util.regex.PatternSyntaxException; |
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/** |
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* The {@code String} class represents character strings. All |
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* string literals in Java programs, such as {@code "abc"}, are |
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* implemented as instances of this class. |
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* <p> |
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* Strings are constant; their values cannot be changed after they |
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* are created. String buffers support mutable strings. |
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* Because String objects are immutable they can be shared. For example: |
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* <blockquote><pre> |
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* String str = "abc"; |
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* </pre></blockquote><p> |
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* is equivalent to: |
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* <blockquote><pre> |
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* char data[] = {'a', 'b', 'c'}; |
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* String str = new String(data); |
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* </pre></blockquote><p> |
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* Here are some more examples of how strings can be used: |
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* <blockquote><pre> |
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* System.out.println("abc"); |
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* String cde = "cde"; |
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* System.out.println("abc" + cde); |
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* String c = "abc".substring(2,3); |
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* String d = cde.substring(1, 2); |
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* </pre></blockquote> |
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* <p> |
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* The class {@code String} includes methods for examining |
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* individual characters of the sequence, for comparing strings, for |
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* searching strings, for extracting substrings, and for creating a |
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* copy of a string with all characters translated to uppercase or to |
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* lowercase. Case mapping is based on the Unicode Standard version |
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* specified by the {@link java.lang.Character Character} class. |
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* <p> |
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* The Java language provides special support for the string |
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* concatenation operator ( + ), and for conversion of |
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* other objects to strings. String concatenation is implemented |
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* through the {@code StringBuilder}(or {@code StringBuffer}) |
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* class and its {@code append} method. |
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* String conversions are implemented through the method |
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* {@code toString}, defined by {@code Object} and |
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* inherited by all classes in Java. For additional information on |
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* string concatenation and conversion, see Gosling, Joy, and Steele, |
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* <i>The Java Language Specification</i>. |
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* |
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* <p> Unless otherwise noted, passing a <tt>null</tt> argument to a constructor |
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* or method in this class will cause a {@link NullPointerException} to be |
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* thrown. |
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* |
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* <p>A {@code String} represents a string in the UTF-16 format |
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* in which <em>supplementary characters</em> are represented by <em>surrogate |
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* pairs</em> (see the section <a href="Character.html#unicode">Unicode |
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* Character Representations</a> in the {@code Character} class for |
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* more information). |
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* Index values refer to {@code char} code units, so a supplementary |
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* character uses two positions in a {@code String}. |
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* <p>The {@code String} class provides methods for dealing with |
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* Unicode code points (i.e., characters), in addition to those for |
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* dealing with Unicode code units (i.e., {@code char} values). |
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* |
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* @author Lee Boynton |
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* @author Arthur van Hoff |
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* @author Martin Buchholz |
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* @author Ulf Zibis |
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* @see java.lang.Object#toString() |
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* @see java.lang.StringBuffer |
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* @see java.lang.StringBuilder |
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* @see java.nio.charset.Charset |
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* @since JDK1.0 |
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*/ |
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public final class String |
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implements java.io.Serializable, Comparable<String>, CharSequence { |
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/** The value is used for character storage. */ |
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private final char value[]; |
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/** Cache the hash code for the string */ |
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private int hash; // Default to 0 |
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/** use serialVersionUID from JDK 1.0.2 for interoperability */ |
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private static final long serialVersionUID = -6849794470754667710L; |
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/** |
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* Class String is special cased within the Serialization Stream Protocol. |
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* |
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* A String instance is written into an ObjectOutputStream according to |
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* <a href="{@docRoot}/../platform/serialization/spec/output.html"> |
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* Object Serialization Specification, Section 6.2, "Stream Elements"</a> |
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*/ |
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private static final ObjectStreamField[] serialPersistentFields = |
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new ObjectStreamField[0]; |
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/** |
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* Initializes a newly created {@code String} object so that it represents |
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* an empty character sequence. Note that use of this constructor is |
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* unnecessary since Strings are immutable. |
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*/ |
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public String() { |
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this.value = "".value; |
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} |
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/** |
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* Initializes a newly created {@code String} object so that it represents |
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* the same sequence of characters as the argument; in other words, the |
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* newly created string is a copy of the argument string. Unless an |
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* explicit copy of {@code original} is needed, use of this constructor is |
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* unnecessary since Strings are immutable. |
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* |
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* @param original |
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* A {@code String} |
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*/ |
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public String(String original) { |
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this.value = original.value; |
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this.hash = original.hash; |
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} |
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/** |
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* Allocates a new {@code String} so that it represents the sequence of |
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* characters currently contained in the character array argument. The |
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* contents of the character array are copied; subsequent modification of |
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* the character array does not affect the newly created string. |
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* |
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* @param value |
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* The initial value of the string |
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*/ |
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public String(char value[]) { |
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this.value = Arrays.copyOf(value, value.length); |
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} |
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/** |
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* Allocates a new {@code String} that contains characters from a subarray |
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* of the character array argument. The {@code offset} argument is the |
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* index of the first character of the subarray and the {@code count} |
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* argument specifies the length of the subarray. The contents of the |
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* subarray are copied; subsequent modification of the character array does |
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* not affect the newly created string. |
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* |
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* @param value |
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* Array that is the source of characters |
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* |
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* @param offset |
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* The initial offset |
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* |
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* @param count |
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* The length |
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* |
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* @throws IndexOutOfBoundsException |
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* If the {@code offset} and {@code count} arguments index |
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* characters outside the bounds of the {@code value} array |
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*/ |
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public String(char value[], int offset, int count) { |
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if (offset < 0) { |
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throw new StringIndexOutOfBoundsException(offset); |
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} |
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if (count <= 0) { |
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if (count < 0) { |
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throw new StringIndexOutOfBoundsException(count); |
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} |
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if (offset <= value.length) { |
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this.value = "".value; |
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return; |
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} |
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} |
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// Note: offset or count might be near -1>>>1. |
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if (offset > value.length - count) { |
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throw new StringIndexOutOfBoundsException(offset + count); |
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} |
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this.value = Arrays.copyOfRange(value, offset, offset+count); |
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} |
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/** |
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* Allocates a new {@code String} that contains characters from a subarray |
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* of the <a href="Character.html#unicode">Unicode code point</a> array |
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* argument. The {@code offset} argument is the index of the first code |
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* point of the subarray and the {@code count} argument specifies the |
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* length of the subarray. The contents of the subarray are converted to |
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* {@code char}s; subsequent modification of the {@code int} array does not |
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* affect the newly created string. |
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* |
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* @param codePoints |
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* Array that is the source of Unicode code points |
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* |
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* @param offset |
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* The initial offset |
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* |
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* @param count |
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* The length |
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* |
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* @throws IllegalArgumentException |
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* If any invalid Unicode code point is found in {@code |
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* codePoints} |
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* |
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* @throws IndexOutOfBoundsException |
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* If the {@code offset} and {@code count} arguments index |
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* characters outside the bounds of the {@code codePoints} array |
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* |
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* @since 1.5 |
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*/ |
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public String(int[] codePoints, int offset, int count) { |
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if (offset < 0) { |
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throw new StringIndexOutOfBoundsException(offset); |
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} |
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if (count <= 0) { |
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if (count < 0) { |
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throw new StringIndexOutOfBoundsException(count); |
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} |
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if (offset <= codePoints.length) { |
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this.value = "".value; |
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return; |
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} |
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} |
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// Note: offset or count might be near -1>>>1. |
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if (offset > codePoints.length - count) { |
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throw new StringIndexOutOfBoundsException(offset + count); |
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} |
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final int end = offset + count; |
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// Pass 1: Compute precise size of char[] |
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int n = count; |
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for (int i = offset; i < end; i++) { |
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int c = codePoints[i]; |
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if (Character.isBmpCodePoint(c)) |
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continue; |
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else if (Character.isValidCodePoint(c)) |
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n++; |
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else throw new IllegalArgumentException(Integer.toString(c)); |
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} |
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// Pass 2: Allocate and fill in char[] |
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final char[] v = new char[n]; |
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for (int i = offset, j = 0; i < end; i++, j++) { |
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int c = codePoints[i]; |
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if (Character.isBmpCodePoint(c)) |
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v[j] = (char)c; |
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else |
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Character.toSurrogates(c, v, j++); |
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} |
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this.value = v; |
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} |
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/** |
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* Allocates a new {@code String} constructed from a subarray of an array |
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* of 8-bit integer values. |
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* |
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* <p> The {@code offset} argument is the index of the first byte of the |
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* subarray, and the {@code count} argument specifies the length of the |
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* subarray. |
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* |
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* <p> Each {@code byte} in the subarray is converted to a {@code char} as |
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* specified in the method above. |
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* |
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* @deprecated This method does not properly convert bytes into characters. |
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* As of JDK 1.1, the preferred way to do this is via the |
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* {@code String} constructors that take a {@link |
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* java.nio.charset.Charset}, charset name, or that use the platform's |
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* default charset. |
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* |
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* @param ascii |
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* The bytes to be converted to characters |
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* |
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* @param hibyte |
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* The top 8 bits of each 16-bit Unicode code unit |
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* |
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* @param offset |
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* The initial offset |
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* @param count |
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* The length |
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* |
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* @throws IndexOutOfBoundsException |
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* If the {@code offset} or {@code count} argument is invalid |
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* |
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* @see #String(byte[], int) |
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* @see #String(byte[], int, int, java.lang.String) |
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* @see #String(byte[], int, int, java.nio.charset.Charset) |
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* @see #String(byte[], int, int) |
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* @see #String(byte[], java.lang.String) |
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* @see #String(byte[], java.nio.charset.Charset) |
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* @see #String(byte[]) |
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*/ |
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@Deprecated |
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public String(byte ascii[], int hibyte, int offset, int count) { |
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checkBounds(ascii, offset, count); |
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char value[] = new char[count]; |
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if (hibyte == 0) { |
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for (int i = count; i-- > 0;) { |
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value[i] = (char)(ascii[i + offset] & 0xff); |
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} |
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} else { |
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hibyte <<= 8; |
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for (int i = count; i-- > 0;) { |
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value[i] = (char)(hibyte | (ascii[i + offset] & 0xff)); |
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} |
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} |
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this.value = value; |
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} |
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/** |
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* Allocates a new {@code String} containing characters constructed from |
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* an array of 8-bit integer values. Each character <i>c</i>in the |
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* resulting string is constructed from the corresponding component |
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* <i>b</i> in the byte array such that: |
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* |
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* <blockquote><pre> |
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* <b><i>c</i></b> == (char)(((hibyte & 0xff) << 8) |
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* | (<b><i>b</i></b> & 0xff)) |
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* </pre></blockquote> |
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* |
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* @deprecated This method does not properly convert bytes into |
|
* characters. As of JDK 1.1, the preferred way to do this is via the |
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* {@code String} constructors that take a {@link |
|
* java.nio.charset.Charset}, charset name, or that use the platform's |
|
* default charset. |
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* |
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* @param ascii |
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* The bytes to be converted to characters |
|
* |
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* @param hibyte |
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* The top 8 bits of each 16-bit Unicode code unit |
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* |
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* @see #String(byte[], int, int, java.lang.String) |
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* @see #String(byte[], int, int, java.nio.charset.Charset) |
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* @see #String(byte[], int, int) |
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* @see #String(byte[], java.lang.String) |
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* @see #String(byte[], java.nio.charset.Charset) |
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* @see #String(byte[]) |
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*/ |
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@Deprecated |
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public String(byte ascii[], int hibyte) { |
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this(ascii, hibyte, 0, ascii.length); |
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} |
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/* Common private utility method used to bounds check the byte array |
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* and requested offset & length values used by the String(byte[],..) |
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* constructors. |
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*/ |
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private static void checkBounds(byte[] bytes, int offset, int length) { |
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if (length < 0) |
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throw new StringIndexOutOfBoundsException(length); |
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if (offset < 0) |
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throw new StringIndexOutOfBoundsException(offset); |
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if (offset > bytes.length - length) |
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throw new StringIndexOutOfBoundsException(offset + length); |
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} |
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/** |
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* Constructs a new {@code String} by decoding the specified subarray of |
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* bytes using the specified charset. The length of the new {@code String} |
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* is a function of the charset, and hence may not be equal to the length |
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* of the subarray. |
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* |
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* <p> The behavior of this constructor when the given bytes are not valid |
|
* in the given charset is unspecified. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
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* over the decoding process is required. |
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* |
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* @param bytes |
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* The bytes to be decoded into characters |
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* |
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* @param offset |
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* The index of the first byte to decode |
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* |
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* @param length |
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* The number of bytes to decode |
|
|
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* @param charsetName |
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* The name of a supported {@linkplain java.nio.charset.Charset |
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* charset} |
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* |
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* @throws UnsupportedEncodingException |
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* If the named charset is not supported |
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* |
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* @throws IndexOutOfBoundsException |
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* If the {@code offset} and {@code length} arguments index |
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* characters outside the bounds of the {@code bytes} array |
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* |
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* @since JDK1.1 |
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*/ |
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public String(byte bytes[], int offset, int length, String charsetName) |
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throws UnsupportedEncodingException { |
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if (charsetName == null) |
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throw new NullPointerException("charsetName"); |
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checkBounds(bytes, offset, length); |
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this.value = StringCoding.decode(charsetName, bytes, offset, length); |
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} |
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/** |
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* Constructs a new {@code String} by decoding the specified subarray of |
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* bytes using the specified {@linkplain java.nio.charset.Charset charset}. |
|
* The length of the new {@code String} is a function of the charset, and |
|
* hence may not be equal to the length of the subarray. |
|
* |
|
* <p> This method always replaces malformed-input and unmappable-character |
|
* sequences with this charset's default replacement string. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
|
* over the decoding process is required. |
|
* |
|
* @param bytes |
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* The bytes to be decoded into characters |
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* |
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* @param offset |
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* The index of the first byte to decode |
|
* |
|
* @param length |
|
* The number of bytes to decode |
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* |
|
* @param charset |
|
* The {@linkplain java.nio.charset.Charset charset} to be used to |
|
* decode the {@code bytes} |
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* |
|
* @throws IndexOutOfBoundsException |
|
* If the {@code offset} and {@code length} arguments index |
|
* characters outside the bounds of the {@code bytes} array |
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* |
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* @since 1.6 |
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*/ |
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public String(byte bytes[], int offset, int length, Charset charset) { |
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if (charset == null) |
|
throw new NullPointerException("charset"); |
|
checkBounds(bytes, offset, length); |
|
this.value = StringCoding.decode(charset, bytes, offset, length); |
|
} |
|
/** |
|
* Constructs a new {@code String} by decoding the specified array of bytes |
|
* using the specified {@linkplain java.nio.charset.Charset charset}. The |
|
* length of the new {@code String} is a function of the charset, and hence |
|
* may not be equal to the length of the byte array. |
|
* |
|
* <p> The behavior of this constructor when the given bytes are not valid |
|
* in the given charset is unspecified. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
|
* over the decoding process is required. |
|
* |
|
* @param bytes |
|
* The bytes to be decoded into characters |
|
* |
|
* @param charsetName |
|
* The name of a supported {@linkplain java.nio.charset.Charset |
|
* charset} |
|
* |
|
* @throws UnsupportedEncodingException |
|
* If the named charset is not supported |
|
* |
|
* @since JDK1.1 |
|
*/ |
|
public String(byte bytes[], String charsetName) |
|
throws UnsupportedEncodingException { |
|
this(bytes, 0, bytes.length, charsetName); |
|
} |
|
/** |
|
* Constructs a new {@code String} by decoding the specified array of |
|
* bytes using the specified {@linkplain java.nio.charset.Charset charset}. |
|
* The length of the new {@code String} is a function of the charset, and |
|
* hence may not be equal to the length of the byte array. |
|
* |
|
* <p> This method always replaces malformed-input and unmappable-character |
|
* sequences with this charset's default replacement string. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
|
* over the decoding process is required. |
|
* |
|
* @param bytes |
|
* The bytes to be decoded into characters |
|
* |
|
* @param charset |
|
* The {@linkplain java.nio.charset.Charset charset} to be used to |
|
* decode the {@code bytes} |
|
* |
|
* @since 1.6 |
|
*/ |
|
public String(byte bytes[], Charset charset) { |
|
this(bytes, 0, bytes.length, charset); |
|
} |
|
/** |
|
* Constructs a new {@code String} by decoding the specified subarray of |
|
* bytes using the platform's default charset. The length of the new |
|
* {@code String} is a function of the charset, and hence may not be equal |
|
* to the length of the subarray. |
|
* |
|
* <p> The behavior of this constructor when the given bytes are not valid |
|
* in the default charset is unspecified. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
|
* over the decoding process is required. |
|
* |
|
* @param bytes |
|
* The bytes to be decoded into characters |
|
* |
|
* @param offset |
|
* The index of the first byte to decode |
|
* |
|
* @param length |
|
* The number of bytes to decode |
|
* |
|
* @throws IndexOutOfBoundsException |
|
* If the {@code offset} and the {@code length} arguments index |
|
* characters outside the bounds of the {@code bytes} array |
|
* |
|
* @since JDK1.1 |
|
*/ |
|
public String(byte bytes[], int offset, int length) { |
|
checkBounds(bytes, offset, length); |
|
this.value = StringCoding.decode(bytes, offset, length); |
|
} |
|
/** |
|
* Constructs a new {@code String} by decoding the specified array of bytes |
|
* using the platform's default charset. The length of the new {@code |
|
* String} is a function of the charset, and hence may not be equal to the |
|
* length of the byte array. |
|
* |
|
* <p> The behavior of this constructor when the given bytes are not valid |
|
* in the default charset is unspecified. The {@link |
|
* java.nio.charset.CharsetDecoder} class should be used when more control |
|
* over the decoding process is required. |
|
* |
|
* @param bytes |
|
* The bytes to be decoded into characters |
|
* |
|
* @since JDK1.1 |
|
*/ |
|
public String(byte bytes[]) { |
|
this(bytes, 0, bytes.length); |
|
} |
|
/** |
|
* Allocates a new string that contains the sequence of characters |
|
* currently contained in the string buffer argument. The contents of the |
|
* string buffer are copied; subsequent modification of the string buffer |
|
* does not affect the newly created string. |
|
* |
|
* @param buffer |
|
* A {@code StringBuffer} |
|
*/ |
|
public String(StringBuffer buffer) { |
|
synchronized(buffer) { |
|
this.value = Arrays.copyOf(buffer.getValue(), buffer.length()); |
|
} |
|
} |
|
/** |
|
* Allocates a new string that contains the sequence of characters |
|
* currently contained in the string builder argument. The contents of the |
|
* string builder are copied; subsequent modification of the string builder |
|
* does not affect the newly created string. |
|
* |
|
* <p> This constructor is provided to ease migration to {@code |
|
* StringBuilder}. Obtaining a string from a string builder via the {@code |
|
* toString} method is likely to run faster and is generally preferred. |
|
* |
|
* @param builder |
|
* A {@code StringBuilder} |
|
* |
|
* @since 1.5 |
|
*/ |
|
public String(StringBuilder builder) { |
|
this.value = Arrays.copyOf(builder.getValue(), builder.length()); |
|
} |
|
/* |
|
* Package private constructor which shares value array for speed. |
|
* this constructor is always expected to be called with share==true. |
|
* a separate constructor is needed because we already have a public |
|
* String(char[]) constructor that makes a copy of the given char[]. |
|
*/ |
|
String(char[] value, boolean share) { |
|
// assert share : "unshared not supported"; |
|
this.value = value; |
|
} |
|
/** |
|
* Returns the length of this string. |
|
* The length is equal to the number of <a href="Character.html#unicode">Unicode |
|
* code units</a> in the string. |
|
* |
|
* @return the length of the sequence of characters represented by this |
|
* object. |
|
*/ |
|
public int length() { |
|
return value.length; |
|
} |
|
/** |
|
* Returns {@code true} if, and only if, {@link #length()} is {@code 0}. |
|
* |
|
* @return {@code true} if {@link #length()} is {@code 0}, otherwise |
|
* {@code false} |
|
* |
|
* @since 1.6 |
|
*/ |
|
public boolean isEmpty() { |
|
return value.length == 0; |
|
} |
|
/** |
|
* Returns the {@code char} value at the |
|
* specified index. An index ranges from {@code 0} to |
|
* {@code length() - 1}. The first {@code char} value of the sequence |
|
* is at index {@code 0}, the next at index {@code 1}, |
|
* and so on, as for array indexing. |
|
* |
|
* <p>If the {@code char} value specified by the index is a |
|
* <a href="Character.html#unicode">surrogate</a>, the surrogate |
|
* value is returned. |
|
* |
|
* @param index the index of the {@code char} value. |
|
* @return the {@code char} value at the specified index of this string. |
|
* The first {@code char} value is at index {@code 0}. |
|
* @exception IndexOutOfBoundsException if the {@code index} |
|
* argument is negative or not less than the length of this |
|
* string. |
|
*/ |
|
public char charAt(int index) { |
|
if ((index < 0) || (index >= value.length)) { |
|
throw new StringIndexOutOfBoundsException(index); |
|
} |
|
return value[index]; |
|
} |
|
/** |
|
* Returns the character (Unicode code point) at the specified |
|
* index. The index refers to {@code char} values |
|
* (Unicode code units) and ranges from {@code 0} to |
|
* {@link #length()}{@code - 1}. |
|
* |
|
* <p> If the {@code char} value specified at the given index |
|
* is in the high-surrogate range, the following index is less |
|
* than the length of this {@code String}, and the |
|
* {@code char} value at the following index is in the |
|
* low-surrogate range, then the supplementary code point |
|
* corresponding to this surrogate pair is returned. Otherwise, |
|
* the {@code char} value at the given index is returned. |
|
* |
|
* @param index the index to the {@code char} values |
|
* @return the code point value of the character at the |
|
* {@code index} |
|
* @exception IndexOutOfBoundsException if the {@code index} |
|
* argument is negative or not less than the length of this |
|
* string. |
|
* @since 1.5 |
|
*/ |
|
public int codePointAt(int index) { |
|
if ((index < 0) || (index >= value.length)) { |
|
throw new StringIndexOutOfBoundsException(index); |
|
} |
|
return Character.codePointAtImpl(value, index, value.length); |
|
} |
|
/** |
|
* Returns the character (Unicode code point) before the specified |
|
* index. The index refers to {@code char} values |
|
* (Unicode code units) and ranges from {@code 1} to {@link |
|
* CharSequence#length() length}. |
|
* |
|
* <p> If the {@code char} value at {@code (index - 1)} |
|
* is in the low-surrogate range, {@code (index - 2)} is not |
|
* negative, and the {@code char} value at {@code (index - |
|
* 2)} is in the high-surrogate range, then the |
|
* supplementary code point value of the surrogate pair is |
|
* returned. If the {@code char} value at {@code index - |
|
* 1} is an unpaired low-surrogate or a high-surrogate, the |
|
* surrogate value is returned. |
|
* |
|
* @param index the index following the code point that should be returned |
|
* @return the Unicode code point value before the given index. |
|
* @exception IndexOutOfBoundsException if the {@code index} |
|
* argument is less than 1 or greater than the length |
|
* of this string. |
|
* @since 1.5 |
|
*/ |
|
public int codePointBefore(int index) { |
|
int i = index - 1; |
|
if ((i < 0) || (i >= value.length)) { |
|
throw new StringIndexOutOfBoundsException(index); |
|
} |
|
return Character.codePointBeforeImpl(value, index, 0); |
|
} |
|
/** |
|
* Returns the number of Unicode code points in the specified text |
|
* range of this {@code String}. The text range begins at the |
|
* specified {@code beginIndex} and extends to the |
|
* {@code char} at index {@code endIndex - 1}. Thus the |
|
* length (in {@code char}s) of the text range is |
|
* {@code endIndex-beginIndex}. Unpaired surrogates within |
|
* the text range count as one code point each. |
|
* |
|
* @param beginIndex the index to the first {@code char} of |
|
* the text range. |
|
* @param endIndex the index after the last {@code char} of |
|
* the text range. |
|
* @return the number of Unicode code points in the specified text |
|
* range |
|
* @exception IndexOutOfBoundsException if the |
|
* {@code beginIndex} is negative, or {@code endIndex} |
|
* is larger than the length of this {@code String}, or |
|
* {@code beginIndex} is larger than {@code endIndex}. |
|
* @since 1.5 |
|
*/ |
|
public int codePointCount(int beginIndex, int endIndex) { |
|
if (beginIndex < 0 || endIndex > value.length || beginIndex > endIndex) { |
|
throw new IndexOutOfBoundsException(); |
|
} |
|
return Character.codePointCountImpl(value, beginIndex, endIndex - beginIndex); |
|
} |
|
/** |
|
* Returns the index within this {@code String} that is |
|
* offset from the given {@code index} by |
|
* {@code codePointOffset} code points. Unpaired surrogates |
|
* within the text range given by {@code index} and |
|
* {@code codePointOffset} count as one code point each. |
|
* |
|
* @param index the index to be offset |
|
* @param codePointOffset the offset in code points |
|
* @return the index within this {@code String} |
|
* @exception IndexOutOfBoundsException if {@code index} |
|
* is negative or larger then the length of this |
|
* {@code String}, or if {@code codePointOffset} is positive |
|
* and the substring starting with {@code index} has fewer |
|
* than {@code codePointOffset} code points, |
|
* or if {@code codePointOffset} is negative and the substring |
|
* before {@code index} has fewer than the absolute value |
|
* of {@code codePointOffset} code points. |
|
* @since 1.5 |
|
*/ |
|
public int offsetByCodePoints(int index, int codePointOffset) { |
|
if (index < 0 || index > value.length) { |
|
throw new IndexOutOfBoundsException(); |
|
} |
|
return Character.offsetByCodePointsImpl(value, 0, value.length, |
|
index, codePointOffset); |
|
} |
|
/** |
|
* Copy characters from this string into dst starting at dstBegin. |
|
* This method doesn't perform any range checking. |
|
*/ |
|
void getChars(char dst[], int dstBegin) { |
|
System.arraycopy(value, 0, dst, dstBegin, value.length); |
|
} |
|
/** |
|
* Copies characters from this string into the destination character |
|
* array. |
|
* <p> |
|
* The first character to be copied is at index {@code srcBegin}; |
|
* the last character to be copied is at index {@code srcEnd-1} |
|
* (thus the total number of characters to be copied is |
|
* {@code srcEnd-srcBegin}). The characters are copied into the |
|
* subarray of {@code dst} starting at index {@code dstBegin} |
|
* and ending at index: |
|
* <blockquote><pre> |
|
* dstBegin + (srcEnd-srcBegin) - 1 |
|
* </pre></blockquote> |
|
* |
|
* @param srcBegin index of the first character in the string |
|
* to copy. |
|
* @param srcEnd index after the last character in the string |
|
* to copy. |
|
* @param dst the destination array. |
|
* @param dstBegin the start offset in the destination array. |
|
* @exception IndexOutOfBoundsException If any of the following |
|
* is true: |
|
* <ul><li>{@code srcBegin} is negative. |
|
* <li>{@code srcBegin} is greater than {@code srcEnd} |
|
* <li>{@code srcEnd} is greater than the length of this |
|
* string |
|
* <li>{@code dstBegin} is negative |
|
* <li>{@code dstBegin+(srcEnd-srcBegin)} is larger than |
|
* {@code dst.length}</ul> |
|
*/ |
|
public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) { |
|
if (srcBegin < 0) { |
|
throw new StringIndexOutOfBoundsException(srcBegin); |
|
} |
|
if (srcEnd > value.length) { |
|
throw new StringIndexOutOfBoundsException(srcEnd); |
|
} |
|
if (srcBegin > srcEnd) { |
|
throw new StringIndexOutOfBoundsException(srcEnd - srcBegin); |
|
} |
|
System.arraycopy(value, srcBegin, dst, dstBegin, srcEnd - srcBegin); |
|
} |
|
/** |
|
* Copies characters from this string into the destination byte array. Each |
|
* byte receives the 8 low-order bits of the corresponding character. The |
|
* eight high-order bits of each character are not copied and do not |
|
* participate in the transfer in any way. |
|
* |
|
* <p> The first character to be copied is at index {@code srcBegin}; the |
|
* last character to be copied is at index {@code srcEnd-1}. The total |
|
* number of characters to be copied is {@code srcEnd-srcBegin}. The |
|
* characters, converted to bytes, are copied into the subarray of {@code |
|
* dst} starting at index {@code dstBegin} and ending at index: |
|
* |
|
* <blockquote><pre> |
|
* dstBegin + (srcEnd-srcBegin) - 1 |
|
* </pre></blockquote> |
|
* |
|
* @deprecated This method does not properly convert characters into |
|
* bytes. As of JDK 1.1, the preferred way to do this is via the |
|
* {@link #getBytes()} method, which uses the platform's default charset. |
|
* |
|
* @param srcBegin |
|
* Index of the first character in the string to copy |
|
* |
|
* @param srcEnd |
|
* Index after the last character in the string to copy |
|
* |
|
* @param dst |
|
* The destination array |
|
* |
|
* @param dstBegin |
|
* The start offset in the destination array |
|
* |
|
* @throws IndexOutOfBoundsException |
|
* If any of the following is true: |
|
* <ul> |
|
* <li> {@code srcBegin} is negative |
|
* <li> {@code srcBegin} is greater than {@code srcEnd} |
|
* <li> {@code srcEnd} is greater than the length of this String |
|
* <li> {@code dstBegin} is negative |
|
* <li> {@code dstBegin+(srcEnd-srcBegin)} is larger than {@code |
|
* dst.length} |
|
* </ul> |
|
*/ |
|
@Deprecated |
|
public void getBytes(int srcBegin, int srcEnd, byte dst[], int dstBegin) { |
|
if (srcBegin < 0) { |
|
throw new StringIndexOutOfBoundsException(srcBegin); |
|
} |
|
if (srcEnd > value.length) { |
|
throw new StringIndexOutOfBoundsException(srcEnd); |
|
} |
|
if (srcBegin > srcEnd) { |
|
throw new StringIndexOutOfBoundsException(srcEnd - srcBegin); |
|
} |
|
Objects.requireNonNull(dst); |
|
int j = dstBegin; |
|
int n = srcEnd; |
|
int i = srcBegin; |
|
char[] val = value; /* avoid getfield opcode */ |
|
while (i < n) { |
|
dst[j++] = (byte)val[i++]; |
|
} |
|
} |
|
/** |
|
* Encodes this {@code String} into a sequence of bytes using the named |
|
* charset, storing the result into a new byte array. |
|
* |
|
* <p> The behavior of this method when this string cannot be encoded in |
|
* the given charset is unspecified. The {@link |
|
* java.nio.charset.CharsetEncoder} class should be used when more control |
|
* over the encoding process is required. |
|
* |
|
* @param charsetName |
|
* The name of a supported {@linkplain java.nio.charset.Charset |
|
* charset} |
|
* |
|
* @return The resultant byte array |
|
* |
|
* @throws UnsupportedEncodingException |
|
* If the named charset is not supported |
|
* |
|
* @since JDK1.1 |
|
*/ |
|
public byte[] getBytes(String charsetName) |
|
throws UnsupportedEncodingException { |
|
if (charsetName == null) throw new NullPointerException(); |
|
return StringCoding.encode(charsetName, value, 0, value.length); |
|
} |
|
/** |
|
* Encodes this {@code String} into a sequence of bytes using the given |
|
* {@linkplain java.nio.charset.Charset charset}, storing the result into a |
|
* new byte array. |
|
* |
|
* <p> This method always replaces malformed-input and unmappable-character |
|
* sequences with this charset's default replacement byte array. The |
|
* {@link java.nio.charset.CharsetEncoder} class should be used when more |
|
* control over the encoding process is required. |
|
* |
|
* @param charset |
|
* The {@linkplain java.nio.charset.Charset} to be used to encode |
|
* the {@code String} |
|
* |
|
* @return The resultant byte array |
|
* |
|
* @since 1.6 |
|
*/ |
|
public byte[] getBytes(Charset charset) { |
|
if (charset == null) throw new NullPointerException(); |
|
return StringCoding.encode(charset, value, 0, value.length); |
|
} |
|
/** |
|
* Encodes this {@code String} into a sequence of bytes using the |
|
* platform's default charset, storing the result into a new byte array. |
|
* |
|
* <p> The behavior of this method when this string cannot be encoded in |
|
* the default charset is unspecified. The {@link |
|
* java.nio.charset.CharsetEncoder} class should be used when more control |
|
* over the encoding process is required. |
|
* |
|
* @return The resultant byte array |
|
* |
|
* @since JDK1.1 |
|
*/ |
|
public byte[] getBytes() { |
|
return StringCoding.encode(value, 0, value.length); |
|
} |
|
/** |
|
* Compares this string to the specified object. The result is {@code |
|
* true} if and only if the argument is not {@code null} and is a {@code |
|
* String} object that represents the same sequence of characters as this |
|
* object. |
|
* |
|
* @param anObject |
|
* The object to compare this {@code String} against |
|
* |
|
* @return {@code true} if the given object represents a {@code String} |
|
* equivalent to this string, {@code false} otherwise |
|
* |
|
* @see #compareTo(String) |
|
* @see #equalsIgnoreCase(String) |
|
*/ |
|
public boolean equals(Object anObject) { |
|
if (this == anObject) { |
|
return true; |
|
} |
|
if (anObject instanceof String) { |
|
String anotherString = (String)anObject; |
|
int n = value.length; |
|
if (n == anotherString.value.length) { |
|
char v1[] = value; |
|
char v2[] = anotherString.value; |
|
int i = 0; |
|
while (n-- != 0) { |
|
if (v1[i] != v2[i]) |
|
return false; |
|
i++; |
|
} |
|
return true; |
|
} |
|
} |
|
return false; |
|
} |
|
/** |
|
* Compares this string to the specified {@code StringBuffer}. The result |
|
* is {@code true} if and only if this {@code String} represents the same |
|
* sequence of characters as the specified {@code StringBuffer}. This method |
|
* synchronizes on the {@code StringBuffer}. |
|
* |
|
* @param sb |
|
* The {@code StringBuffer} to compare this {@code String} against |
|
* |
|
* @return {@code true} if this {@code String} represents the same |
|
* sequence of characters as the specified {@code StringBuffer}, |
|
* {@code false} otherwise |
|
* |
|
* @since 1.4 |
|
*/ |
|
public boolean contentEquals(StringBuffer sb) { |
|
return contentEquals((CharSequence)sb); |
|
} |
|
private boolean nonSyncContentEquals(AbstractStringBuilder sb) { |
|
char v1[] = value; |
|
char v2[] = sb.getValue(); |
|
int n = v1.length; |
|
if (n != sb.length()) { |
|
return false; |
|
} |
|
for (int i = 0; i < n; i++) { |
|
if (v1[i] != v2[i]) { |
|
return false; |
|
} |
|
} |
|
return true; |
|
} |
|
/** |
|
* Compares this string to the specified {@code CharSequence}. The |
|
* result is {@code true} if and only if this {@code String} represents the |
|
* same sequence of char values as the specified sequence. Note that if the |
|
* {@code CharSequence} is a {@code StringBuffer} then the method |
|
* synchronizes on it. |
|
* |
|
* @param cs |
|
* The sequence to compare this {@code String} against |
|
* |
|
* @return {@code true} if this {@code String} represents the same |
|
* sequence of char values as the specified sequence, {@code |
|
* false} otherwise |
|
* |
|
* @since 1.5 |
|
*/ |
|
public boolean contentEquals(CharSequence cs) { |
|
// Argument is a StringBuffer, StringBuilder |
|
if (cs instanceof AbstractStringBuilder) { |
|
if (cs instanceof StringBuffer) { |
|
synchronized(cs) { |
|
return nonSyncContentEquals((AbstractStringBuilder)cs); |
|
} |
|
} else { |
|
return nonSyncContentEquals((AbstractStringBuilder)cs); |
|
} |
|
} |
|
// Argument is a String |
|
if (cs instanceof String) { |
|
return equals(cs); |
|
} |
|
// Argument is a generic CharSequence |
|
char v1[] = value; |
|
int n = v1.length; |
|
if (n != cs.length()) { |
|
return false; |
|
} |
|
for (int i = 0; i < n; i++) { |
|
if (v1[i] != cs.charAt(i)) { |
|
return false; |
|
} |
|
} |
|
return true; |
|
} |
|
/** |
|
* Compares this {@code String} to another {@code String}, ignoring case |
|
* considerations. Two strings are considered equal ignoring case if they |
|
* are of the same length and corresponding characters in the two strings |
|
* are equal ignoring case. |
|
* |
|
* <p> Two characters {@code c1} and {@code c2} are considered the same |
|
* ignoring case if at least one of the following is true: |
|
* <ul> |
|
* <li> The two characters are the same (as compared by the |
|
* {@code ==} operator) |
|
* <li> Applying the method {@link |
|
* java.lang.Character#toUpperCase(char)} to each character |
|
* produces the same result |
|
* <li> Applying the method {@link |
|
* java.lang.Character#toLowerCase(char)} to each character |
|
* produces the same result |
|
* </ul> |
|
* |
|
* @param anotherString |
|
* The {@code String} to compare this {@code String} against |
|
* |
|
* @return {@code true} if the argument is not {@code null} and it |
|
* represents an equivalent {@code String} ignoring case; {@code |
|
* false} otherwise |
|
* |
|
* @see #equals(Object) |
|
*/ |
|
public boolean equalsIgnoreCase(String anotherString) { |
|
return (this == anotherString) ? true |
|
: (anotherString != null) |
|
&& (anotherString.value.length == value.length) |
|
&& regionMatches(true, 0, anotherString, 0, value.length); |
|
} |
|
/** |
|
* Compares two strings lexicographically. |
|
* The comparison is based on the Unicode value of each character in |
|
* the strings. The character sequence represented by this |
|
* {@code String} object is compared lexicographically to the |
|
* character sequence represented by the argument string. The result is |
|
* a negative integer if this {@code String} object |
|
* lexicographically precedes the argument string. The result is a |
|
* positive integer if this {@code String} object lexicographically |
|
* follows the argument string. The result is zero if the strings |
|
* are equal; {@code compareTo} returns {@code 0} exactly when |
|
* the {@link #equals(Object)} method would return {@code true}. |
|
* <p> |
|
* This is the definition of lexicographic ordering. If two strings are |
|
* different, then either they have different characters at some index |
|
* that is a valid index for both strings, or their lengths are different, |
|
* or both. If they have different characters at one or more index |
|
* positions, let <i>k</i> be the smallest such index; then the string |
|
* whose character at position <i>k</i> has the smaller value, as |
|
* determined by using the < operator, lexicographically precedes the |
|
* other string. In this case, {@code compareTo} returns the |
|
* difference of the two character values at position {@code k} in |
|
* the two string -- that is, the value: |
|
* <blockquote><pre> |
|
* this.charAt(k)-anotherString.charAt(k) |
|
* </pre></blockquote> |
|
* If there is no index position at which they differ, then the shorter |
|
* string lexicographically precedes the longer string. In this case, |
|
* {@code compareTo} returns the difference of the lengths of the |
|
* strings -- that is, the value: |
|
* <blockquote><pre> |
|
* this.length()-anotherString.length() |
|
* </pre></blockquote> |
|
* |
|
* @param anotherString the {@code String} to be compared. |
|
* @return the value {@code 0} if the argument string is equal to |
|
* this string; a value less than {@code 0} if this string |
|
* is lexicographically less than the string argument; and a |
|
* value greater than {@code 0} if this string is |
|
* lexicographically greater than the string argument. |
|
*/ |
|
public int compareTo(String anotherString) { |
|
int len1 = value.length; |
|
int len2 = anotherString.value.length; |
|
int lim = Math.min(len1, len2); |
|
char v1[] = value; |
|
char v2[] = anotherString.value; |
|
int k = 0; |
|
while (k < lim) { |
|
char c1 = v1[k]; |
|
char c2 = v2[k]; |
|
if (c1 != c2) { |
|
return c1 - c2; |
|
} |
|
k++; |
|
} |
|
return len1 - len2; |
|
} |
|
/** |
|
* A Comparator that orders {@code String} objects as by |
|
* {@code compareToIgnoreCase}. This comparator is serializable. |
|
* <p> |
|
* Note that this Comparator does <em>not</em> take locale into account, |
|
* and will result in an unsatisfactory ordering for certain locales. |
|
* The java.text package provides <em>Collators</em> to allow |
|
* locale-sensitive ordering. |
|
* |
|
* @see java.text.Collator#compare(String, String) |
|
* @since 1.2 |
|
*/ |
|
public static final Comparator<String> CASE_INSENSITIVE_ORDER |
|
= new CaseInsensitiveComparator(); |
|
private static class CaseInsensitiveComparator |
|
implements Comparator<String>, java.io.Serializable { |
|
// use serialVersionUID from JDK 1.2.2 for interoperability |
|
private static final long serialVersionUID = 8575799808933029326L; |
|
public int compare(String s1, String s2) { |
|
int n1 = s1.length(); |
|
int n2 = s2.length(); |
|
int min = Math.min(n1, n2); |
|
for (int i = 0; i < min; i++) { |
|
char c1 = s1.charAt(i); |
|
char c2 = s2.charAt(i); |
|
if (c1 != c2) { |
|
c1 = Character.toUpperCase(c1); |
|
c2 = Character.toUpperCase(c2); |
|
if (c1 != c2) { |
|
c1 = Character.toLowerCase(c1); |
|
c2 = Character.toLowerCase(c2); |
|
if (c1 != c2) { |
|
// No overflow because of numeric promotion |
|
return c1 - c2; |
|
} |
|
} |
|
} |
|
} |
|
return n1 - n2; |
|
} |
|
/** Replaces the de-serialized object. */ |
|
private Object readResolve() { return CASE_INSENSITIVE_ORDER; } |
|
} |
|
/** |
|
* Compares two strings lexicographically, ignoring case |
|
* differences. This method returns an integer whose sign is that of |
|
* calling {@code compareTo} with normalized versions of the strings |
|
* where case differences have been eliminated by calling |
|
* {@code Character.toLowerCase(Character.toUpperCase(character))} on |
|
* each character. |
|
* <p> |
|
* Note that this method does <em>not</em> take locale into account, |
|
* and will result in an unsatisfactory ordering for certain locales. |
|
* The java.text package provides <em>collators</em> to allow |
|
* locale-sensitive ordering. |
|
* |
|
* @param str the {@code String} to be compared. |
|
* @return a negative integer, zero, or a positive integer as the |
|
* specified String is greater than, equal to, or less |
|
* than this String, ignoring case considerations. |
|
* @see java.text.Collator#compare(String, String) |
|
* @since 1.2 |
|
*/ |
|
public int compareToIgnoreCase(String str) { |
|
return CASE_INSENSITIVE_ORDER.compare(this, str); |
|
} |
|
/** |
|
* Tests if two string regions are equal. |
|
* <p> |
|
* A substring of this {@code String} object is compared to a substring |
|
* of the argument other. The result is true if these substrings |
|
* represent identical character sequences. The substring of this |
|
* {@code String} object to be compared begins at index {@code toffset} |
|
* and has length {@code len}. The substring of other to be compared |
|
* begins at index {@code ooffset} and has length {@code len}. The |
|
* result is {@code false} if and only if at least one of the following |
|
* is true: |
|
* <ul><li>{@code toffset} is negative. |
|
* <li>{@code ooffset} is negative. |
|
* <li>{@code toffset+len} is greater than the length of this |
|
* {@code String} object. |
|
* <li>{@code ooffset+len} is greater than the length of the other |
|
* argument. |
|
* <li>There is some nonnegative integer <i>k</i> less than {@code len} |
|
* such that: |
|
* {@code this.charAt(toffset + }<i>k</i>{@code ) != other.charAt(ooffset + } |
|
* <i>k</i>{@code )} |
|
* </ul> |
|
* |
|
* @param toffset the starting offset of the subregion in this string. |
|
* @param other the string argument. |
|
* @param ooffset the starting offset of the subregion in the string |
|
* argument. |
|
* @param len the number of characters to compare. |
|
* @return {@code true} if the specified subregion of this string |
|
* exactly matches the specified subregion of the string argument; |
|
* {@code false} otherwise. |
|
*/ |
|
public boolean regionMatches(int toffset, String other, int ooffset, |
|
int len) { |
|
char ta[] = value; |
|
int to = toffset; |
|
char pa[] = other.value; |
|
int po = ooffset; |
|
// Note: toffset, ooffset, or len might be near -1>>>1. |
|
if ((ooffset < 0) || (toffset < 0) |
|
|| (toffset > (long)value.length - len) |
|
|| (ooffset > (long)other.value.length - len)) { |
|
return false; |
|
} |
|
while (len-- > 0) { |
|
if (ta[to++] != pa[po++]) { |
|
return false; |
|
} |
|
} |
|
return true; |
|
} |
|
/** |
|
* Tests if two string regions are equal. |
|
* <p> |
|
* A substring of this {@code String} object is compared to a substring |
|
* of the argument {@code other}. The result is {@code true} if these |
|
* substrings represent character sequences that are the same, ignoring |
|
* case if and only if {@code ignoreCase} is true. The substring of |
|
* this {@code String} object to be compared begins at index |
|
* {@code toffset} and has length {@code len}. The substring of |
|
* {@code other} to be compared begins at index {@code ooffset} and |
|
* has length {@code len}. The result is {@code false} if and only if |
|
* at least one of the following is true: |
|
* <ul><li>{@code toffset} is negative. |
|
* <li>{@code ooffset} is negative. |
|
* <li>{@code toffset+len} is greater than the length of this |
|
* {@code String} object. |
|
* <li>{@code ooffset+len} is greater than the length of the other |
|
* argument. |
|
* <li>{@code ignoreCase} is {@code false} and there is some nonnegative |
|
* integer <i>k</i> less than {@code len} such that: |
|
* <blockquote><pre> |
|
* this.charAt(toffset+k) != other.charAt(ooffset+k) |
|
* </pre></blockquote> |
|
* <li>{@code ignoreCase} is {@code true} and there is some nonnegative |
|
* integer <i>k</i> less than {@code len} such that: |
|
* <blockquote><pre> |
|
* Character.toLowerCase(this.charAt(toffset+k)) != |
|
Character.toLowerCase(other.charAt(ooffset+k)) |
|
* </pre></blockquote> |
|
* and: |
|
* <blockquote><pre> |
|
* Character.toUpperCase(this.charAt(toffset+k)) != |
|
* Character.toUpperCase(other.charAt(ooffset+k)) |
|
* </pre></blockquote> |
|
* </ul> |
|
* |
|
* @param ignoreCase if {@code true}, ignore case when comparing |
|
* characters. |
|
* @param toffset the starting offset of the subregion in this |
|
* string. |
|
* @param other the string argument. |
|
* @param ooffset the starting offset of the subregion in the string |
|
* argument. |
|
* @param len the number of characters to compare. |
|
* @return {@code true} if the specified subregion of this string |
|
* matches the specified subregion of the string argument; |
|
* {@code false} otherwise. Whether the matching is exact |
|
* or case insensitive depends on the {@code ignoreCase} |
|
* argument. |
|
*/ |
|
public boolean regionMatches(boolean ignoreCase, int toffset, |
|
String other, int ooffset, int len) { |
|
char ta[] = value; |
|
int to = toffset; |
|
char pa[] = other.value; |
|
int po = ooffset; |
|
// Note: toffset, ooffset, or len might be near -1>>>1. |
|
if ((ooffset < 0) || (toffset < 0) |
|
|| (toffset > (long)value.length - len) |
|
|| (ooffset > (long)other.value.length - len)) { |
|
return false; |
|
} |
|
while (len-- > 0) { |
|
char c1 = ta[to++]; |
|
char c2 = pa[po++]; |
|
if (c1 == c2) { |
|
continue; |
|
} |
|
if (ignoreCase) { |
|
// If characters don't match but case may be ignored, |
|
// try converting both characters to uppercase. |
|
// If the results match, then the comparison scan should |
|
// continue. |
|
char u1 = Character.toUpperCase(c1); |
|
char u2 = Character.toUpperCase(c2); |
|
if (u1 == u2) { |
|
continue; |
|
} |
|
// Unfortunately, conversion to uppercase does not work properly |
|
// for the Georgian alphabet, which has strange rules about case |
|
// conversion. So we need to make one last check before |
|
// exiting. |
|
if (Character.toLowerCase(u1) == Character.toLowerCase(u2)) { |
|
continue; |
|
} |
|
} |
|
return false; |
|
} |
|
return true; |
|
} |
|
/** |
|
* Tests if the substring of this string beginning at the |
|
* specified index starts with the specified prefix. |
|
* |
|
* @param prefix the prefix. |
|
* @param toffset where to begin looking in this string. |
|
* @return {@code true} if the character sequence represented by the |
|
* argument is a prefix of the substring of this object starting |
|
* at index {@code toffset}; {@code false} otherwise. |
|
* The result is {@code false} if {@code toffset} is |
|
* negative or greater than the length of this |
|
* {@code String} object; otherwise the result is the same |
|
* as the result of the expression |
|
* <pre> |
|
* this.substring(toffset).startsWith(prefix) |
|
* </pre> |
|
*/ |
|
public boolean startsWith(String prefix, int toffset) { |
|
char ta[] = value; |
|
int to = toffset; |
|
char pa[] = prefix.value; |
|
int po = 0; |
|
int pc = prefix.value.length; |
|
// Note: toffset might be near -1>>>1. |
|
if ((toffset < 0) || (toffset > value.length - pc)) { |
|
return false; |
|
} |
|
while (--pc >= 0) { |
|
if (ta[to++] != pa[po++]) { |
|
return false; |
|
} |
|
} |
|
return true; |
|
} |
|
/** |
|
* Tests if this string starts with the specified prefix. |
|
* |
|
* @param prefix the prefix. |
|
* @return {@code true} if the character sequence represented by the |
|
* argument is a prefix of the character sequence represented by |
|
* this string; {@code false} otherwise. |
|
* Note also that {@code true} will be returned if the |
|
* argument is an empty string or is equal to this |
|
* {@code String} object as determined by the |
|
* {@link #equals(Object)} method. |
|
* @since 1. 0 |
|
*/ |
|
public boolean startsWith(String prefix) { |
|
return startsWith(prefix, 0); |
|
} |
|
/** |
|
* Tests if this string ends with the specified suffix. |
|
* |
|
* @param suffix the suffix. |
|
* @return {@code true} if the character sequence represented by the |
|
* argument is a suffix of the character sequence represented by |
|
* this object; {@code false} otherwise. Note that the |
|
* result will be {@code true} if the argument is the |
|
* empty string or is equal to this {@code String} object |
|
* as determined by the {@link #equals(Object)} method. |
|
*/ |
|
public boolean endsWith(String suffix) { |
|
return startsWith(suffix, value.length - suffix.value.length); |
|
} |
|
/** |
|
* Returns a hash code for this string. The hash code for a |
|
* {@code String} object is computed as |
|
* <blockquote><pre> |
|
* s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1] |
|
* </pre></blockquote> |
|
* using {@code int} arithmetic, where {@code s[i]} is the |
|
* <i>i</i>th character of the string, {@code n} is the length of |
|
* the string, and {@code ^} indicates exponentiation. |
|
* (The hash value of the empty string is zero.) |
|
* |
|
* @return a hash code value for this object. |
|
*/ |
|
public int hashCode() { |
|
int h = hash; |
|
if (h == 0 && value.length > 0) { |
|
char val[] = value; |
|
for (int i = 0; i < value.length; i++) { |
|
h = 31 * h + val[i]; |
|
} |
|
hash = h; |
|
} |
|
return h; |
|
} |
|
/** |
|
* Returns the index within this string of the first occurrence of |
|
* the specified character. If a character with value |
|
* {@code ch} occurs in the character sequence represented by |
|
* this {@code String} object, then the index (in Unicode |
|
* code units) of the first such occurrence is returned. For |
|
* values of {@code ch} in the range from 0 to 0xFFFF |
|
* (inclusive), this is the smallest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* this.charAt(<i>k</i>) == ch |
|
* </pre></blockquote> |
|
* is true. For other values of {@code ch}, it is the |
|
* smallest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* this.codePointAt(<i>k</i>) == ch |
|
* </pre></blockquote> |
|
* is true. In either case, if no such character occurs in this |
|
* string, then {@code -1} is returned. |
|
* |
|
* @param ch a character (Unicode code point). |
|
* @return the index of the first occurrence of the character in the |
|
* character sequence represented by this object, or |
|
* {@code -1} if the character does not occur. |
|
*/ |
|
public int indexOf(int ch) { |
|
return indexOf(ch, 0); |
|
} |
|
/** |
|
* Returns the index within this string of the first occurrence of the |
|
* specified character, starting the search at the specified index. |
|
* <p> |
|
* If a character with value {@code ch} occurs in the |
|
* character sequence represented by this {@code String} |
|
* object at an index no smaller than {@code fromIndex}, then |
|
* the index of the first such occurrence is returned. For values |
|
* of {@code ch} in the range from 0 to 0xFFFF (inclusive), |
|
* this is the smallest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* (this.charAt(<i>k</i>) == ch) {@code &&} (<i>k</i> >= fromIndex) |
|
* </pre></blockquote> |
|
* is true. For other values of {@code ch}, it is the |
|
* smallest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* (this.codePointAt(<i>k</i>) == ch) {@code &&} (<i>k</i> >= fromIndex) |
|
* </pre></blockquote> |
|
* is true. In either case, if no such character occurs in this |
|
* string at or after position {@code fromIndex}, then |
|
* {@code -1} is returned. |
|
* |
|
* <p> |
|
* There is no restriction on the value of {@code fromIndex}. If it |
|
* is negative, it has the same effect as if it were zero: this entire |
|
* string may be searched. If it is greater than the length of this |
|
* string, it has the same effect as if it were equal to the length of |
|
* this string: {@code -1} is returned. |
|
* |
|
* <p>All indices are specified in {@code char} values |
|
* (Unicode code units). |
|
* |
|
* @param ch a character (Unicode code point). |
|
* @param fromIndex the index to start the search from. |
|
* @return the index of the first occurrence of the character in the |
|
* character sequence represented by this object that is greater |
|
* than or equal to {@code fromIndex}, or {@code -1} |
|
* if the character does not occur. |
|
*/ |
|
public int indexOf(int ch, int fromIndex) { |
|
final int max = value.length; |
|
if (fromIndex < 0) { |
|
fromIndex = 0; |
|
} else if (fromIndex >= max) { |
|
// Note: fromIndex might be near -1>>>1. |
|
return -1; |
|
} |
|
if (ch < Character.MIN_SUPPLEMENTARY_CODE_POINT) { |
|
// handle most cases here (ch is a BMP code point or a |
|
// negative value (invalid code point)) |
|
final char[] value = this.value; |
|
for (int i = fromIndex; i < max; i++) { |
|
if (value[i] == ch) { |
|
return i; |
|
} |
|
} |
|
return -1; |
|
} else { |
|
return indexOfSupplementary(ch, fromIndex); |
|
} |
|
} |
|
/** |
|
* Handles (rare) calls of indexOf with a supplementary character. |
|
*/ |
|
private int indexOfSupplementary(int ch, int fromIndex) { |
|
if (Character.isValidCodePoint(ch)) { |
|
final char[] value = this.value; |
|
final char hi = Character.highSurrogate(ch); |
|
final char lo = Character.lowSurrogate(ch); |
|
final int max = value.length - 1; |
|
for (int i = fromIndex; i < max; i++) { |
|
if (value[i] == hi && value[i + 1] == lo) { |
|
return i; |
|
} |
|
} |
|
} |
|
return -1; |
|
} |
|
/** |
|
* Returns the index within this string of the last occurrence of |
|
* the specified character. For values of {@code ch} in the |
|
* range from 0 to 0xFFFF (inclusive), the index (in Unicode code |
|
* units) returned is the largest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* this.charAt(<i>k</i>) == ch |
|
* </pre></blockquote> |
|
* is true. For other values of {@code ch}, it is the |
|
* largest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* this.codePointAt(<i>k</i>) == ch |
|
* </pre></blockquote> |
|
* is true. In either case, if no such character occurs in this |
|
* string, then {@code -1} is returned. The |
|
* {@code String} is searched backwards starting at the last |
|
* character. |
|
* |
|
* @param ch a character (Unicode code point). |
|
* @return the index of the last occurrence of the character in the |
|
* character sequence represented by this object, or |
|
* {@code -1} if the character does not occur. |
|
*/ |
|
public int lastIndexOf(int ch) { |
|
return lastIndexOf(ch, value.length - 1); |
|
} |
|
/** |
|
* Returns the index within this string of the last occurrence of |
|
* the specified character, searching backward starting at the |
|
* specified index. For values of {@code ch} in the range |
|
* from 0 to 0xFFFF (inclusive), the index returned is the largest |
|
* value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* (this.charAt(<i>k</i>) == ch) {@code &&} (<i>k</i> <= fromIndex) |
|
* </pre></blockquote> |
|
* is true. For other values of {@code ch}, it is the |
|
* largest value <i>k</i> such that: |
|
* <blockquote><pre> |
|
* (this.codePointAt(<i>k</i>) == ch) {@code &&} (<i>k</i> <= fromIndex) |
|
* </pre></blockquote> |
|
* is true. In either case, if no such character occurs in this |
|
* string at or before position {@code fromIndex}, then |
|
* {@code -1} is returned. |
|
* |
|
* <p>All indices are specified in {@code char} values |
|
* (Unicode code units). |
|
* |
|
* @param ch a character (Unicode code point). |
|
* @param fromIndex the index to start the search from. There is no |
|
* restriction on the value of {@code fromIndex}. If it is |
|
* greater than or equal to the length of this string, it has |
|
* the same effect as if it were equal to one less than the |
|
* length of this string: this entire string may be searched. |
|
* If it is negative, it has the same effect as if it were -1: |
|
* -1 is returned. |
|
* @return the index of the last occurrence of the character in the |
|
* character sequence represented by this object that is less |
|
* than or equal to {@code fromIndex}, or {@code -1} |
|
* if the character does not occur before that point. |
|
*/ |
|
public int lastIndexOf(int ch, int fromIndex) { |
|
if (ch < Character.MIN_SUPPLEMENTARY_CODE_POINT) { |
|
// handle most cases here (ch is a BMP code point or a |
|
// negative value (invalid code point)) |
|
final char[] value = this.value; |
|
int i = Math.min(fromIndex, value.length - 1); |
|
for (; i >= 0; i--) { |
|
if (value[i] == ch) { |
|
return i; |
|
} |
|
} |
|
return -1; |
|
} else { |
|
return lastIndexOfSupplementary(ch, fromIndex); |
|
} |
|
} |
|
/** |
|
* Handles (rare) calls of lastIndexOf with a supplementary character. |
|
*/ |
|
private int lastIndexOfSupplementary(int ch, int fromIndex) { |
|
if (Character.isValidCodePoint(ch)) { |
|
final char[] value = this.value; |
|
char hi = Character.highSurrogate(ch); |
|
char lo = Character.lowSurrogate(ch); |
|
int i = Math.min(fromIndex, value.length - 2); |
|
for (; i >= 0; i--) { |
|
if (value[i] == hi && value[i + 1] == lo) { |
|
return i; |
|
} |
|
} |
|
} |
|
return -1; |
|
} |
|
/** |
|
* Returns the index within this string of the first occurrence of the |
|
* specified substring. |
|
* |
|
* <p>The returned index is the smallest value <i>k</i> for which: |
|
* <blockquote><pre> |
|
* this.startsWith(str, <i>k</i>) |
|
* </pre></blockquote> |
|
* If no such value of <i>k</i> exists, then {@code -1} is returned. |
|
* |
|
* @param str the substring to search for. |
|
* @return the index of the first occurrence of the specified substring, |
|
* or {@code -1} if there is no such occurrence. |
|
*/ |
|
public int indexOf(String str) { |
|
return indexOf(str, 0); |
|
} |
|
/** |
|
* Returns the index within this string of the first occurrence of the |
|
* specified substring, starting at the specified index. |
|
* |
|
* <p>The returned index is the smallest value <i>k</i> for which: |
|
* <blockquote><pre> |
|
* <i>k</i> >= fromIndex {@code &&} this.startsWith(str, <i>k</i>) |
|
* </pre></blockquote> |
|
* If no such value of <i>k</i> exists, then {@code -1} is returned. |
|
* |
|
* @param str the substring to search for. |
|
* @param fromIndex the index from which to start the search. |
|
* @return the index of the first occurrence of the specified substring, |
|
* starting at the specified index, |
|
* or {@code -1} if there is no such occurrence. |
|
*/ |
|
public int indexOf(String str, int fromIndex) { |
|
return indexOf(value, 0, value.length, |
|
str.value, 0, str.value.length, fromIndex); |
|
} |
|
/** |
|
* Code shared by String and AbstractStringBuilder to do searches. The |
|
* source is the character array being searched, and the target |
|
* is the string being searched for. |
|
* |
|
* @param source the characters being searched. |
|
* @param sourceOffset offset of the source string. |
|
* @param sourceCount count of the source string. |
|
* @param target the characters being searched for. |
|
* @param fromIndex the index to begin searching from. |
|
*/ |
|
static int indexOf(char[] source, int sourceOffset, int sourceCount, |
|
String target, int fromIndex) { |
|
return indexOf(source, sourceOffset, sourceCount, |
|
target.value, 0, target.value.length, |
|
fromIndex); |
|
} |
|
/** |
|
* Code shared by String and StringBuffer to do searches. The |
|
* source is the character array being searched, and the target |
|
* is the string being searched for. |
|
* |
|
* @param source the characters being searched. |
|
* @param sourceOffset offset of the source string. |
|
* @param sourceCount count of the source string. |
|
* @param target the characters being searched for. |
|
* @param targetOffset offset of the target string. |
|
* @param targetCount count of the target string. |
|
* @param fromIndex the index to begin searching from. |
|
*/ |
|
static int indexOf(char[] source, int sourceOffset, int sourceCount, |
|
char[] target, int targetOffset, int targetCount, |
|
int fromIndex) { |
|
if (fromIndex >= sourceCount) { |
|
return (targetCount == 0 ? sourceCount : -1); |
|
} |
|
if (fromIndex < 0) { |
|
fromIndex = 0; |
|
} |
|
if (targetCount == 0) { |
|
return fromIndex; |
|
} |
|
char first = target[targetOffset]; |
|
int max = sourceOffset + (sourceCount - targetCount); |
|
for (int i = sourceOffset + fromIndex; i <= max; i++) { |
|
/* Look for first character. */ |
|
if (source[i] != first) { |
|
while (++i <= max && source[i] != first); |
|
} |
|
/* Found first character, now look at the rest of v2 */ |
|
if (i <= max) { |
|
int j = i + 1; |
|
int end = j + targetCount - 1; |
|
for (int k = targetOffset + 1; j < end && source[j] |
|
== target[k]; j++, k++); |
|
if (j == end) { |
|
/* Found whole string. */ |
|
return i - sourceOffset; |
|
} |
|
} |
|
} |
|
return -1; |
|
} |
|
/** |
|
* Returns the index within this string of the last occurrence of the |
|
* specified substring. The last occurrence of the empty string "" |
|
* is considered to occur at the index value {@code this.length()}. |
|
* |
|
* <p>The returned index is the largest value <i>k</i> for which: |
|
* <blockquote><pre> |
|
* this.startsWith(str, <i>k</i>) |
|
* </pre></blockquote> |
|
* If no such value of <i>k</i> exists, then {@code -1} is returned. |
|
* |
|
* @param str the substring to search for. |
|
* @return the index of the last occurrence of the specified substring, |
|
* or {@code -1} if there is no such occurrence. |
|
*/ |
|
public int lastIndexOf(String str) { |
|
return lastIndexOf(str, value.length); |
|
} |
|
/** |
|
* Returns the index within this string of the last occurrence of the |
|
* specified substring, searching backward starting at the specified index. |
|
* |
|
* <p>The returned index is the largest value <i>k</i> for which: |
|
* <blockquote><pre> |
|
* <i>k</i> {@code <=} fromIndex {@code &&} this.startsWith(str, <i>k</i>) |
|
* </pre></blockquote> |
|
* If no such value of <i>k</i> exists, then {@code -1} is returned. |
|
* |
|
* @param str the substring to search for. |
|
* @param fromIndex the index to start the search from. |
|
* @return the index of the last occurrence of the specified substring, |
|
* searching backward from the specified index, |
|
* or {@code -1} if there is no such occurrence. |
|
*/ |
|
public int lastIndexOf(String str, int fromIndex) { |
|
return lastIndexOf(value, 0, value.length, |
|
str.value, 0, str.value.length, fromIndex); |
|
} |
|
/** |
|
* Code shared by String and AbstractStringBuilder to do searches. The |
|
* source is the character array being searched, and the target |
|
* is the string being searched for. |
|
* |
|
* @param source the characters being searched. |
|
* @param sourceOffset offset of the source string. |
|
* @param sourceCount count of the source string. |
|
* @param target the characters being searched for. |
|
* @param fromIndex the index to begin searching from. |
|
*/ |
|
static int lastIndexOf(char[] source, int sourceOffset, int sourceCount, |
|
String target, int fromIndex) { |
|
return lastIndexOf(source, sourceOffset, sourceCount, |
|
target.value, 0, target.value.length, |
|
fromIndex); |
|
} |
|
/** |
|
* Code shared by String and StringBuffer to do searches. The |
|
* source is the character array being searched, and the target |
|
* is the string being searched for. |
|
* |
|
* @param source the characters being searched. |
|
* @param sourceOffset offset of the source string. |
|
* @param sourceCount count of the source string. |
|
* @param target the characters being searched for. |
|
* @param targetOffset offset of the target string. |
|
* @param targetCount count of the target string. |
|
* @param fromIndex the index to begin searching from. |
|
*/ |
|
static int lastIndexOf(char[] source, int sourceOffset, int sourceCount, |
|
char[] target, int targetOffset, int targetCount, |
|
int fromIndex) { |
|
/* |
|
* Check arguments; return immediately where possible. For |
|
* consistency, don't check for null str. |
|
*/ |
|
int rightIndex = sourceCount - targetCount; |
|
if (fromIndex < 0) { |
|
return -1; |
|
} |
|
if (fromIndex > rightIndex) { |
|
fromIndex = rightIndex; |
|
} |
|
/* Empty string always matches. */ |
|
if (targetCount == 0) { |
|
return fromIndex; |
|
} |
|
int strLastIndex = targetOffset + targetCount - 1; |
|
char strLastChar = target[strLastIndex]; |
|
int min = sourceOffset + targetCount - 1; |
|
int i = min + fromIndex; |
|
startSearchForLastChar: |
|
while (true) { |
|
while (i >= min && source[i] != strLastChar) { |
|
i--; |
|
} |
|
if (i < min) { |
|
return -1; |
|
} |
|
int j = i - 1; |
|
int start = j - (targetCount - 1); |
|
int k = strLastIndex - 1; |
|
while (j > start) { |
|
if (source[j--] != target[k--]) { |
|
i--; |
|
continue startSearchForLastChar; |
|
} |
|
} |
|
return start - sourceOffset + 1; |
|
} |
|
} |
|
/** |
|
* Returns a string that is a substring of this string. The |
|
* substring begins with the character at the specified index and |
|
* extends to the end of this string. <p> |
|
* Examples: |
|
* <blockquote><pre> |
|
* "unhappy".substring(2) returns "happy" |
|
* "Harbison".substring(3) returns "bison" |
|
* "emptiness".substring(9) returns "" (an empty string) |
|
* </pre></blockquote> |
|
* |
|
* @param beginIndex the beginning index, inclusive. |
|
* @return the specified substring. |
|
* @exception IndexOutOfBoundsException if |
|
* {@code beginIndex} is negative or larger than the |
|
* length of this {@code String} object. |
|
*/ |
|
public String substring(int beginIndex) { |
|
if (beginIndex < 0) { |
|
throw new StringIndexOutOfBoundsException(beginIndex); |
|
} |
|
int subLen = value.length - beginIndex; |
|
if (subLen < 0) { |
|
throw new StringIndexOutOfBoundsException(subLen); |
|
} |
|
return (beginIndex == 0) ? this : new String(value, beginIndex, subLen); |
|
} |
|
/** |
|
* Returns a string that is a substring of this string. The |
|
* substring begins at the specified {@code beginIndex} and |
|
* extends to the character at index {@code endIndex - 1}. |
|
* Thus the length of the substring is {@code endIndex-beginIndex}. |
|
* <p> |
|
* Examples: |
|
* <blockquote><pre> |
|
* "hamburger".substring(4, 8) returns "urge" |
|
* "smiles".substring(1, 5) returns "mile" |
|
* </pre></blockquote> |
|
* |
|
* @param beginIndex the beginning index, inclusive. |
|
* @param endIndex the ending index, exclusive. |
|
* @return the specified substring. |
|
* @exception IndexOutOfBoundsException if the |
|
* {@code beginIndex} is negative, or |
|
* {@code endIndex} is larger than the length of |
|
* this {@code String} object, or |
|
* {@code beginIndex} is larger than |
|
* {@code endIndex}. |
|
*/ |
|
public String substring(int beginIndex, int endIndex) { |
|
if (beginIndex < 0) { |
|
throw new StringIndexOutOfBoundsException(beginIndex); |
|
} |
|
if (endIndex > value.length) { |
|
throw new StringIndexOutOfBoundsException(endIndex); |
|
} |
|
int subLen = endIndex - beginIndex; |
|
if (subLen < 0) { |
|
throw new StringIndexOutOfBoundsException(subLen); |
|
} |
|
return ((beginIndex == 0) && (endIndex == value.length)) ? this |
|
: new String(value, beginIndex, subLen); |
|
} |
|
/** |
|
* Returns a character sequence that is a subsequence of this sequence. |
|
* |
|
* <p> An invocation of this method of the form |
|
* |
|
* <blockquote><pre> |
|
* str.subSequence(begin, end)</pre></blockquote> |
|
* |
|
* behaves in exactly the same way as the invocation |
|
* |
|
* <blockquote><pre> |
|
* str.substring(begin, end)</pre></blockquote> |
|
* |
|
* @apiNote |
|
* This method is defined so that the {@code String} class can implement |
|
* the {@link CharSequence} interface. |
|
* |
|
* @param beginIndex the begin index, inclusive. |
|
* @param endIndex the end index, exclusive. |
|
* @return the specified subsequence. |
|
* |
|
* @throws IndexOutOfBoundsException |
|
* if {@code beginIndex} or {@code endIndex} is negative, |
|
* if {@code endIndex} is greater than {@code length()}, |
|
* or if {@code beginIndex} is greater than {@code endIndex} |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public CharSequence subSequence(int beginIndex, int endIndex) { |
|
return this.substring(beginIndex, endIndex); |
|
} |
|
/** |
|
* Concatenates the specified string to the end of this string. |
|
* <p> |
|
* If the length of the argument string is {@code 0}, then this |
|
* {@code String} object is returned. Otherwise, a |
|
* {@code String} object is returned that represents a character |
|
* sequence that is the concatenation of the character sequence |
|
* represented by this {@code String} object and the character |
|
* sequence represented by the argument string.<p> |
|
* Examples: |
|
* <blockquote><pre> |
|
* "cares".concat("s") returns "caress" |
|
* "to".concat("get").concat("her") returns "together" |
|
* </pre></blockquote> |
|
* |
|
* @param str the {@code String} that is concatenated to the end |
|
* of this {@code String}. |
|
* @return a string that represents the concatenation of this object's |
|
* characters followed by the string argument's characters. |
|
*/ |
|
public String concat(String str) { |
|
int otherLen = str.length(); |
|
if (otherLen == 0) { |
|
return this; |
|
} |
|
int len = value.length; |
|
char buf[] = Arrays.copyOf(value, len + otherLen); |
|
str.getChars(buf, len); |
|
return new String(buf, true); |
|
} |
|
/** |
|
* Returns a string resulting from replacing all occurrences of |
|
* {@code oldChar} in this string with {@code newChar}. |
|
* <p> |
|
* If the character {@code oldChar} does not occur in the |
|
* character sequence represented by this {@code String} object, |
|
* then a reference to this {@code String} object is returned. |
|
* Otherwise, a {@code String} object is returned that |
|
* represents a character sequence identical to the character sequence |
|
* represented by this {@code String} object, except that every |
|
* occurrence of {@code oldChar} is replaced by an occurrence |
|
* of {@code newChar}. |
|
* <p> |
|
* Examples: |
|
* <blockquote><pre> |
|
* "mesquite in your cellar".replace('e', 'o') |
|
* returns "mosquito in your collar" |
|
* "the war of baronets".replace('r', 'y') |
|
* returns "the way of bayonets" |
|
* "sparring with a purple porpoise".replace('p', 't') |
|
* returns "starring with a turtle tortoise" |
|
* "JonL".replace('q', 'x') returns "JonL" (no change) |
|
* </pre></blockquote> |
|
* |
|
* @param oldChar the old character. |
|
* @param newChar the new character. |
|
* @return a string derived from this string by replacing every |
|
* occurrence of {@code oldChar} with {@code newChar}. |
|
*/ |
|
public String replace(char oldChar, char newChar) { |
|
if (oldChar != newChar) { |
|
int len = value.length; |
|
int i = -1; |
|
char[] val = value; /* avoid getfield opcode */ |
|
while (++i < len) { |
|
if (val[i] == oldChar) { |
|
break; |
|
} |
|
} |
|
if (i < len) { |
|
char buf[] = new char[len]; |
|
for (int j = 0; j < i; j++) { |
|
buf[j] = val[j]; |
|
} |
|
while (i < len) { |
|
char c = val[i]; |
|
buf[i] = (c == oldChar) ? newChar : c; |
|
i++; |
|
} |
|
return new String(buf, true); |
|
} |
|
} |
|
return this; |
|
} |
|
/** |
|
* Tells whether or not this string matches the given <a |
|
* href="../util/regex/Pattern.html#sum">regular expression</a>. |
|
* |
|
* <p> An invocation of this method of the form |
|
* <i>str</i>{@code .matches(}<i>regex</i>{@code )} yields exactly the |
|
* same result as the expression |
|
* |
|
* <blockquote> |
|
* {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#matches(String,CharSequence) |
|
* matches(<i>regex</i>, <i>str</i>)} |
|
* </blockquote> |
|
* |
|
* @param regex |
|
* the regular expression to which this string is to be matched |
|
* |
|
* @return {@code true} if, and only if, this string matches the |
|
* given regular expression |
|
* |
|
* @throws PatternSyntaxException |
|
* if the regular expression's syntax is invalid |
|
* |
|
* @see java.util.regex.Pattern |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public boolean matches(String regex) { |
|
return Pattern.matches(regex, this); |
|
} |
|
/** |
|
* Returns true if and only if this string contains the specified |
|
* sequence of char values. |
|
* |
|
* @param s the sequence to search for |
|
* @return true if this string contains {@code s}, false otherwise |
|
* @since 1.5 |
|
*/ |
|
public boolean contains(CharSequence s) { |
|
return indexOf(s.toString()) > -1; |
|
} |
|
/** |
|
* Replaces the first substring of this string that matches the given <a |
|
* href="../util/regex/Pattern.html#sum">regular expression</a> with the |
|
* given replacement. |
|
* |
|
* <p> An invocation of this method of the form |
|
* <i>str</i>{@code .replaceFirst(}<i>regex</i>{@code ,} <i>repl</i>{@code )} |
|
* yields exactly the same result as the expression |
|
* |
|
* <blockquote> |
|
* <code> |
|
* {@link java.util.regex.Pattern}.{@link |
|
* java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
|
* java.util.regex.Pattern#matcher(java.lang.CharSequence) matcher}(<i>str</i>).{@link |
|
* java.util.regex.Matcher#replaceFirst replaceFirst}(<i>repl</i>) |
|
* </code> |
|
* </blockquote> |
|
* |
|
*<p> |
|
* Note that backslashes ({@code \}) and dollar signs ({@code $}) in the |
|
* replacement string may cause the results to be different than if it were |
|
* being treated as a literal replacement string; see |
|
* {@link java.util.regex.Matcher#replaceFirst}. |
|
* Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special |
|
* meaning of these characters, if desired. |
|
* |
|
* @param regex |
|
* the regular expression to which this string is to be matched |
|
* @param replacement |
|
* the string to be substituted for the first match |
|
* |
|
* @return The resulting {@code String} |
|
* |
|
* @throws PatternSyntaxException |
|
* if the regular expression's syntax is invalid |
|
* |
|
* @see java.util.regex.Pattern |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public String replaceFirst(String regex, String replacement) { |
|
return Pattern.compile(regex).matcher(this).replaceFirst(replacement); |
|
} |
|
/** |
|
* Replaces each substring of this string that matches the given <a |
|
* href="../util/regex/Pattern.html#sum">regular expression</a> with the |
|
* given replacement. |
|
* |
|
* <p> An invocation of this method of the form |
|
* <i>str</i>{@code .replaceAll(}<i>regex</i>{@code ,} <i>repl</i>{@code )} |
|
* yields exactly the same result as the expression |
|
* |
|
* <blockquote> |
|
* <code> |
|
* {@link java.util.regex.Pattern}.{@link |
|
* java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
|
* java.util.regex.Pattern#matcher(java.lang.CharSequence) matcher}(<i>str</i>).{@link |
|
* java.util.regex.Matcher#replaceAll replaceAll}(<i>repl</i>) |
|
* </code> |
|
* </blockquote> |
|
* |
|
*<p> |
|
* Note that backslashes ({@code \}) and dollar signs ({@code $}) in the |
|
* replacement string may cause the results to be different than if it were |
|
* being treated as a literal replacement string; see |
|
* {@link java.util.regex.Matcher#replaceAll Matcher.replaceAll}. |
|
* Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special |
|
* meaning of these characters, if desired. |
|
* |
|
* @param regex |
|
* the regular expression to which this string is to be matched |
|
* @param replacement |
|
* the string to be substituted for each match |
|
* |
|
* @return The resulting {@code String} |
|
* |
|
* @throws PatternSyntaxException |
|
* if the regular expression's syntax is invalid |
|
* |
|
* @see java.util.regex.Pattern |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public String replaceAll(String regex, String replacement) { |
|
return Pattern.compile(regex).matcher(this).replaceAll(replacement); |
|
} |
|
/** |
|
* Replaces each substring of this string that matches the literal target |
|
* sequence with the specified literal replacement sequence. The |
|
* replacement proceeds from the beginning of the string to the end, for |
|
* example, replacing "aa" with "b" in the string "aaa" will result in |
|
* "ba" rather than "ab". |
|
* |
|
* @param target The sequence of char values to be replaced |
|
* @param replacement The replacement sequence of char values |
|
* @return The resulting string |
|
* @since 1.5 |
|
*/ |
|
public String replace(CharSequence target, CharSequence replacement) { |
|
return Pattern.compile(target.toString(), Pattern.LITERAL).matcher( |
|
this).replaceAll(Matcher.quoteReplacement(replacement.toString())); |
|
} |
|
/** |
|
* Splits this string around matches of the given |
|
* <a href="../util/regex/Pattern.html#sum">regular expression</a>. |
|
* |
|
* <p> The array returned by this method contains each substring of this |
|
* string that is terminated by another substring that matches the given |
|
* expression or is terminated by the end of the string. The substrings in |
|
* the array are in the order in which they occur in this string. If the |
|
* expression does not match any part of the input then the resulting array |
|
* has just one element, namely this string. |
|
* |
|
* <p> When there is a positive-width match at the beginning of this |
|
* string then an empty leading substring is included at the beginning |
|
* of the resulting array. A zero-width match at the beginning however |
|
* never produces such empty leading substring. |
|
* |
|
* <p> The {@code limit} parameter controls the number of times the |
|
* pattern is applied and therefore affects the length of the resulting |
|
* array. If the limit <i>n</i> is greater than zero then the pattern |
|
* will be applied at most <i>n</i> - 1 times, the array's |
|
* length will be no greater than <i>n</i>, and the array's last entry |
|
* will contain all input beyond the last matched delimiter. If <i>n</i> |
|
* is non-positive then the pattern will be applied as many times as |
|
* possible and the array can have any length. If <i>n</i> is zero then |
|
* the pattern will be applied as many times as possible, the array can |
|
* have any length, and trailing empty strings will be discarded. |
|
* |
|
* <p> The string {@code "boo:and:foo"}, for example, yields the |
|
* following results with these parameters: |
|
* |
|
* <blockquote><table cellpadding=1 cellspacing=0 summary="Split example showing regex, limit, and result"> |
|
* <tr> |
|
* <th>Regex</th> |
|
* <th>Limit</th> |
|
* <th>Result</th> |
|
* </tr> |
|
* <tr><td align=center>:</td> |
|
* <td align=center>2</td> |
|
* <td>{@code { "boo", "and:foo" }}</td></tr> |
|
* <tr><td align=center>:</td> |
|
* <td align=center>5</td> |
|
* <td>{@code { "boo", "and", "foo" }}</td></tr> |
|
* <tr><td align=center>:</td> |
|
* <td align=center>-2</td> |
|
* <td>{@code { "boo", "and", "foo" }}</td></tr> |
|
* <tr><td align=center>o</td> |
|
* <td align=center>5</td> |
|
* <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
|
* <tr><td align=center>o</td> |
|
* <td align=center>-2</td> |
|
* <td>{@code { "b", "", ":and:f", "", "" }}</td></tr> |
|
* <tr><td align=center>o</td> |
|
* <td align=center>0</td> |
|
* <td>{@code { "b", "", ":and:f" }}</td></tr> |
|
* </table></blockquote> |
|
* |
|
* <p> An invocation of this method of the form |
|
* <i>str.</i>{@code split(}<i>regex</i>{@code ,} <i>n</i>{@code )} |
|
* yields the same result as the expression |
|
* |
|
* <blockquote> |
|
* <code> |
|
* {@link java.util.regex.Pattern}.{@link |
|
* java.util.regex.Pattern#compile compile}(<i>regex</i>).{@link |
|
* java.util.regex.Pattern#split(java.lang.CharSequence,int) split}(<i>str</i>, <i>n</i>) |
|
* </code> |
|
* </blockquote> |
|
* |
|
* |
|
* @param regex |
|
* the delimiting regular expression |
|
* |
|
* @param limit |
|
* the result threshold, as described above |
|
* |
|
* @return the array of strings computed by splitting this string |
|
* around matches of the given regular expression |
|
* |
|
* @throws PatternSyntaxException |
|
* if the regular expression's syntax is invalid |
|
* |
|
* @see java.util.regex.Pattern |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public String[] split(String regex, int limit) { |
|
/* fastpath if the regex is a |
|
(1)one-char String and this character is not one of the |
|
RegEx's meta characters ".$|()[{^?*+\\", or |
|
(2)two-char String and the first char is the backslash and |
|
the second is not the ascii digit or ascii letter. |
|
*/ |
|
char ch = 0; |
|
if (((regex.value.length == 1 && |
|
".$|()[{^?*+\\".indexOf(ch = regex.charAt(0)) == -1) || |
|
(regex.length() == 2 && |
|
regex.charAt(0) == '\\' && |
|
(((ch = regex.charAt(1))-'0')|('9'-ch)) < 0 && |
|
((ch-'a')|('z'-ch)) < 0 && |
|
((ch-'A')|('Z'-ch)) < 0)) && |
|
(ch < Character.MIN_HIGH_SURROGATE || |
|
ch > Character.MAX_LOW_SURROGATE)) |
|
{ |
|
int off = 0; |
|
int next = 0; |
|
boolean limited = limit > 0; |
|
ArrayList<String> list = new ArrayList<>(); |
|
while ((next = indexOf(ch, off)) != -1) { |
|
if (!limited || list.size() < limit - 1) { |
|
list.add(substring(off, next)); |
|
off = next + 1; |
|
} else { // last one |
|
//assert (list.size() == limit - 1); |
|
list.add(substring(off, value.length)); |
|
off = value.length; |
|
break; |
|
} |
|
} |
|
// If no match was found, return this |
|
if (off == 0) |
|
return new String[]{this}; |
|
// Add remaining segment |
|
if (!limited || list.size() < limit) |
|
list.add(substring(off, value.length)); |
|
// Construct result |
|
int resultSize = list.size(); |
|
if (limit == 0) { |
|
while (resultSize > 0 && list.get(resultSize - 1).length() == 0) { |
|
resultSize--; |
|
} |
|
} |
|
String[] result = new String[resultSize]; |
|
return list.subList(0, resultSize).toArray(result); |
|
} |
|
return Pattern.compile(regex).split(this, limit); |
|
} |
|
/** |
|
* Splits this string around matches of the given <a |
|
* href="../util/regex/Pattern.html#sum">regular expression</a>. |
|
* |
|
* <p> This method works as if by invoking the two-argument {@link |
|
* #split(String, int) split} method with the given expression and a limit |
|
* argument of zero. Trailing empty strings are therefore not included in |
|
* the resulting array. |
|
* |
|
* <p> The string {@code "boo:and:foo"}, for example, yields the following |
|
* results with these expressions: |
|
* |
|
* <blockquote><table cellpadding=1 cellspacing=0 summary="Split examples showing regex and result"> |
|
* <tr> |
|
* <th>Regex</th> |
|
* <th>Result</th> |
|
* </tr> |
|
* <tr><td align=center>:</td> |
|
* <td>{@code { "boo", "and", "foo" }}</td></tr> |
|
* <tr><td align=center>o</td> |
|
* <td>{@code { "b", "", ":and:f" }}</td></tr> |
|
* </table></blockquote> |
|
* |
|
* |
|
* @param regex |
|
* the delimiting regular expression |
|
* |
|
* @return the array of strings computed by splitting this string |
|
* around matches of the given regular expression |
|
* |
|
* @throws PatternSyntaxException |
|
* if the regular expression's syntax is invalid |
|
* |
|
* @see java.util.regex.Pattern |
|
* |
|
* @since 1.4 |
|
* @spec JSR-51 |
|
*/ |
|
public String[] split(String regex) { |
|
return split(regex, 0); |
|
} |
|
/** |
|
* Returns a new String composed of copies of the |
|
* {@code CharSequence elements} joined together with a copy of |
|
* the specified {@code delimiter}. |
|
* |
|
* <blockquote>For example, |
|
* <pre>{@code |
|
* String message = String.join("-", "Java", "is", "cool"); |
|
* // message returned is: "Java-is-cool" |
|
* }</pre></blockquote> |
|
* |
|
* Note that if an element is null, then {@code "null"} is added. |
|
* |
|
* @param delimiter the delimiter that separates each element |
|
* @param elements the elements to join together. |
|
* |
|
* @return a new {@code String} that is composed of the {@code elements} |
|
* separated by the {@code delimiter} |
|
* |
|
* @throws NullPointerException If {@code delimiter} or {@code elements} |
|
* is {@code null} |
|
* |
|
* @see java.util.StringJoiner |
|
* @since 1.8 |
|
*/ |
|
public static String join(CharSequence delimiter, CharSequence... elements) { |
|
Objects.requireNonNull(delimiter); |
|
Objects.requireNonNull(elements); |
|
// Number of elements not likely worth Arrays.stream overhead. |
|
StringJoiner joiner = new StringJoiner(delimiter); |
|
for (CharSequence cs: elements) { |
|
joiner.add(cs); |
|
} |
|
return joiner.toString(); |
|
} |
|
/** |
|
* Returns a new {@code String} composed of copies of the |
|
* {@code CharSequence elements} joined together with a copy of the |
|
* specified {@code delimiter}. |
|
* |
|
* <blockquote>For example, |
|
* <pre>{@code |
|
* List<String> strings = new LinkedList<>(); |
|
* strings.add("Java");strings.add("is"); |
|
* strings.add("cool"); |
|
* String message = String.join(" ", strings); |
|
* //message returned is: "Java is cool" |
|
* |
|
* Set<String> strings = new LinkedHashSet<>(); |
|
* strings.add("Java"); strings.add("is"); |
|
* strings.add("very"); strings.add("cool"); |
|
* String message = String.join("-", strings); |
|
* //message returned is: "Java-is-very-cool" |
|
* }</pre></blockquote> |
|
* |
|
* Note that if an individual element is {@code null}, then {@code "null"} is added. |
|
* |
|
* @param delimiter a sequence of characters that is used to separate each |
|
* of the {@code elements} in the resulting {@code String} |
|
* @param elements an {@code Iterable} that will have its {@code elements} |
|
* joined together. |
|
* |
|
* @return a new {@code String} that is composed from the {@code elements} |
|
* argument |
|
* |
|
* @throws NullPointerException If {@code delimiter} or {@code elements} |
|
* is {@code null} |
|
* |
|
* @see #join(CharSequence,CharSequence...) |
|
* @see java.util.StringJoiner |
|
* @since 1.8 |
|
*/ |
|
public static String join(CharSequence delimiter, |
|
Iterable<? extends CharSequence> elements) { |
|
Objects.requireNonNull(delimiter); |
|
Objects.requireNonNull(elements); |
|
StringJoiner joiner = new StringJoiner(delimiter); |
|
for (CharSequence cs: elements) { |
|
joiner.add(cs); |
|
} |
|
return joiner.toString(); |
|
} |
|
/** |
|
* Converts all of the characters in this {@code String} to lower |
|
* case using the rules of the given {@code Locale}. Case mapping is based |
|
* on the Unicode Standard version specified by the {@link java.lang.Character Character} |
|
* class. Since case mappings are not always 1:1 char mappings, the resulting |
|
* {@code String} may be a different length than the original {@code String}. |
|
* <p> |
|
* Examples of lowercase mappings are in the following table: |
|
* <table border="1" summary="Lowercase mapping examples showing language code of locale, upper case, lower case, and description"> |
|
* <tr> |
|
* <th>Language Code of Locale</th> |
|
* <th>Upper Case</th> |
|
* <th>Lower Case</th> |
|
* <th>Description</th> |
|
* </tr> |
|
* <tr> |
|
* <td>tr (Turkish)</td> |
|
* <td>\u0130</td> |
|
* <td>\u0069</td> |
|
* <td>capital letter I with dot above -> small letter i</td> |
|
* </tr> |
|
* <tr> |
|
* <td>tr (Turkish)</td> |
|
* <td>\u0049</td> |
|
* <td>\u0131</td> |
|
* <td>capital letter I -> small letter dotless i </td> |
|
* </tr> |
|
* <tr> |
|
* <td>(all)</td> |
|
* <td>French Fries</td> |
|
* <td>french fries</td> |
|
* <td>lowercased all chars in String</td> |
|
* </tr> |
|
* <tr> |
|
* <td>(all)</td> |
|
* <td><img src="doc-files/capiota.gif" alt="capiota"><img src="doc-files/capchi.gif" alt="capchi"> |
|
* <img src="doc-files/captheta.gif" alt="captheta"><img src="doc-files/capupsil.gif" alt="capupsil"> |
|
* <img src="doc-files/capsigma.gif" alt="capsigma"></td> |
|
* <td><img src="doc-files/iota.gif" alt="iota"><img src="doc-files/chi.gif" alt="chi"> |
|
* <img src="doc-files/theta.gif" alt="theta"><img src="doc-files/upsilon.gif" alt="upsilon"> |
|
* <img src="doc-files/sigma1.gif" alt="sigma"></td> |
|
* <td>lowercased all chars in String</td> |
|
* </tr> |
|
* </table> |
|
* |
|
* @param locale use the case transformation rules for this locale |
|
* @return the {@code String}, converted to lowercase. |
|
* @see java.lang.String#toLowerCase() |
|
* @see java.lang.String#toUpperCase() |
|
* @see java.lang.String#toUpperCase(Locale) |
|
* @since 1.1 |
|
*/ |
|
public String toLowerCase(Locale locale) { |
|
if (locale == null) { |
|
throw new NullPointerException(); |
|
} |
|
int firstUpper; |
|
final int len = value.length; |
|
/* Now check if there are any characters that need to be changed. */ |
|
scan: { |
|
for (firstUpper = 0 ; firstUpper < len; ) { |
|
char c = value[firstUpper]; |
|
if ((c >= Character.MIN_HIGH_SURROGATE) |
|
&& (c <= Character.MAX_HIGH_SURROGATE)) { |
|
int supplChar = codePointAt(firstUpper); |
|
if (supplChar != Character.toLowerCase(supplChar)) { |
|
break scan; |
|
} |
|
firstUpper += Character.charCount(supplChar); |
|
} else { |
|
if (c != Character.toLowerCase(c)) { |
|
break scan; |
|
} |
|
firstUpper++; |
|
} |
|
} |
|
return this; |
|
} |
|
char[] result = new char[len]; |
|
int resultOffset = 0; /* result may grow, so i+resultOffset |
|
* is the write location in result */ |
|
/* Just copy the first few lowerCase characters. */ |
|
System.arraycopy(value, 0, result, 0, firstUpper); |
|
String lang = locale.getLanguage(); |
|
boolean localeDependent = |
|
(lang == "tr" || lang == "az" || lang == "lt"); |
|
char[] lowerCharArray; |
|
int lowerChar; |
|
int srcChar; |
|
int srcCount; |
|
for (int i = firstUpper; i < len; i += srcCount) { |
|
srcChar = (int)value[i]; |
|
if ((char)srcChar >= Character.MIN_HIGH_SURROGATE |
|
&& (char)srcChar <= Character.MAX_HIGH_SURROGATE) { |
|
srcChar = codePointAt(i); |
|
srcCount = Character.charCount(srcChar); |
|
} else { |
|
srcCount = 1; |
|
} |
|
if (localeDependent || |
|
srcChar == '\u03A3' || // GREEK CAPITAL LETTER SIGMA |
|
srcChar == '\u0130') { // LATIN CAPITAL LETTER I WITH DOT ABOVE |
|
lowerChar = ConditionalSpecialCasing.toLowerCaseEx(this, i, locale); |
|
} else { |
|
lowerChar = Character.toLowerCase(srcChar); |
|
} |
|
if ((lowerChar == Character.ERROR) |
|
|| (lowerChar >= Character.MIN_SUPPLEMENTARY_CODE_POINT)) { |
|
if (lowerChar == Character.ERROR) { |
|
lowerCharArray = |
|
ConditionalSpecialCasing.toLowerCaseCharArray(this, i, locale); |
|
} else if (srcCount == 2) { |
|
resultOffset += Character.toChars(lowerChar, result, i + resultOffset) - srcCount; |
|
continue; |
|
} else { |
|
lowerCharArray = Character.toChars(lowerChar); |
|
} |
|
/* Grow result if needed */ |
|
int mapLen = lowerCharArray.length; |
|
if (mapLen > srcCount) { |
|
char[] result2 = new char[result.length + mapLen - srcCount]; |
|
System.arraycopy(result, 0, result2, 0, i + resultOffset); |
|
result = result2; |
|
} |
|
for (int x = 0; x < mapLen; ++x) { |
|
result[i + resultOffset + x] = lowerCharArray[x]; |
|
} |
|
resultOffset += (mapLen - srcCount); |
|
} else { |
|
result[i + resultOffset] = (char)lowerChar; |
|
} |
|
} |
|
return new String(result, 0, len + resultOffset); |
|
} |
|
/** |
|
* Converts all of the characters in this {@code String} to lower |
|
* case using the rules of the default locale. This is equivalent to calling |
|
* {@code toLowerCase(Locale.getDefault())}. |
|
* <p> |
|
* <b>Note:</b> This method is locale sensitive, and may produce unexpected |
|
* results if used for strings that are intended to be interpreted locale |
|
* independently. |
|
* Examples are programming language identifiers, protocol keys, and HTML |
|
* tags. |
|
* For instance, {@code "TITLE".toLowerCase()} in a Turkish locale |
|
* returns {@code "t\u005Cu0131tle"}, where '\u005Cu0131' is the |
|
* LATIN SMALL LETTER DOTLESS I character. |
|
* To obtain correct results for locale insensitive strings, use |
|
* {@code toLowerCase(Locale.ROOT)}. |
|
* <p> |
|
* @return the {@code String}, converted to lowercase. |
|
* @see java.lang.String#toLowerCase(Locale) |
|
*/ |
|
public String toLowerCase() { |
|
return toLowerCase(Locale.getDefault()); |
|
} |
|
/** |
|
* Converts all of the characters in this {@code String} to upper |
|
* case using the rules of the given {@code Locale}. Case mapping is based |
|
* on the Unicode Standard version specified by the {@link java.lang.Character Character} |
|
* class. Since case mappings are not always 1:1 char mappings, the resulting |
|
* {@code String} may be a different length than the original {@code String}. |
|
* <p> |
|
* Examples of locale-sensitive and 1:M case mappings are in the following table. |
|
* |
|
* <table border="1" summary="Examples of locale-sensitive and 1:M case mappings. Shows Language code of locale, lower case, upper case, and description."> |
|
* <tr> |
|
* <th>Language Code of Locale</th> |
|
* <th>Lower Case</th> |
|
* <th>Upper Case</th> |
|
* <th>Description</th> |
|
* </tr> |
|
* <tr> |
|
* <td>tr (Turkish)</td> |
|
* <td>\u0069</td> |
|
* <td>\u0130</td> |
|
* <td>small letter i -> capital letter I with dot above</td> |
|
* </tr> |
|
* <tr> |
|
* <td>tr (Turkish)</td> |
|
* <td>\u0131</td> |
|
* <td>\u0049</td> |
|
* <td>small letter dotless i -> capital letter I</td> |
|
* </tr> |
|
* <tr> |
|
* <td>(all)</td> |
|
* <td>\u00df</td> |
|
* <td>\u0053 \u0053</td> |
|
* <td>small letter sharp s -> two letters: SS</td> |
|
* </tr> |
|
* <tr> |
|
* <td>(all)</td> |
|
* <td>Fahrvergnügen</td> |
|
* <td>FAHRVERGNÜGEN</td> |
|
* <td></td> |
|
* </tr> |
|
* </table> |
|
* @param locale use the case transformation rules for this locale |
|
* @return the {@code String}, converted to uppercase. |
|
* @see java.lang.String#toUpperCase() |
|
* @see java.lang.String#toLowerCase() |
|
* @see java.lang.String#toLowerCase(Locale) |
|
* @since 1.1 |
|
*/ |
|
public String toUpperCase(Locale locale) { |
|
if (locale == null) { |
|
throw new NullPointerException(); |
|
} |
|
int firstLower; |
|
final int len = value.length; |
|
/* Now check if there are any characters that need to be changed. */ |
|
scan: { |
|
for (firstLower = 0 ; firstLower < len; ) { |
|
int c = (int)value[firstLower]; |
|
int srcCount; |
|
if ((c >= Character.MIN_HIGH_SURROGATE) |
|
&& (c <= Character.MAX_HIGH_SURROGATE)) { |
|
c = codePointAt(firstLower); |
|
srcCount = Character.charCount(c); |
|
} else { |
|
srcCount = 1; |
|
} |
|
int upperCaseChar = Character.toUpperCaseEx(c); |
|
if ((upperCaseChar == Character.ERROR) |
|
|| (c != upperCaseChar)) { |
|
break scan; |
|
} |
|
firstLower += srcCount; |
|
} |
|
return this; |
|
} |
|
/* result may grow, so i+resultOffset is the write location in result */ |
|
int resultOffset = 0; |
|
char[] result = new char[len]; /* may grow */ |
|
/* Just copy the first few upperCase characters. */ |
|
System.arraycopy(value, 0, result, 0, firstLower); |
|
String lang = locale.getLanguage(); |
|
boolean localeDependent = |
|
(lang == "tr" || lang == "az" || lang == "lt"); |
|
char[] upperCharArray; |
|
int upperChar; |
|
int srcChar; |
|
int srcCount; |
|
for (int i = firstLower; i < len; i += srcCount) { |
|
srcChar = (int)value[i]; |
|
if ((char)srcChar >= Character.MIN_HIGH_SURROGATE && |
|
(char)srcChar <= Character.MAX_HIGH_SURROGATE) { |
|
srcChar = codePointAt(i); |
|
srcCount = Character.charCount(srcChar); |
|
} else { |
|
srcCount = 1; |
|
} |
|
if (localeDependent) { |
|
upperChar = ConditionalSpecialCasing.toUpperCaseEx(this, i, locale); |
|
} else { |
|
upperChar = Character.toUpperCaseEx(srcChar); |
|
} |
|
if ((upperChar == Character.ERROR) |
|
|| (upperChar >= Character.MIN_SUPPLEMENTARY_CODE_POINT)) { |
|
if (upperChar == Character.ERROR) { |
|
if (localeDependent) { |
|
upperCharArray = |
|
ConditionalSpecialCasing.toUpperCaseCharArray(this, i, locale); |
|
} else { |
|
upperCharArray = Character.toUpperCaseCharArray(srcChar); |
|
} |
|
} else if (srcCount == 2) { |
|
resultOffset += Character.toChars(upperChar, result, i + resultOffset) - srcCount; |
|
continue; |
|
} else { |
|
upperCharArray = Character.toChars(upperChar); |
|
} |
|
/* Grow result if needed */ |
|
int mapLen = upperCharArray.length; |
|
if (mapLen > srcCount) { |
|
char[] result2 = new char[result.length + mapLen - srcCount]; |
|
System.arraycopy(result, 0, result2, 0, i + resultOffset); |
|
result = result2; |
|
} |
|
for (int x = 0; x < mapLen; ++x) { |
|
result[i + resultOffset + x] = upperCharArray[x]; |
|
} |
|
resultOffset += (mapLen - srcCount); |
|
} else { |
|
result[i + resultOffset] = (char)upperChar; |
|
} |
|
} |
|
return new String(result, 0, len + resultOffset); |
|
} |
|
/** |
|
* Converts all of the characters in this {@code String} to upper |
|
* case using the rules of the default locale. This method is equivalent to |
|
* {@code toUpperCase(Locale.getDefault())}. |
|
* <p> |
|
* <b>Note:</b> This method is locale sensitive, and may produce unexpected |
|
* results if used for strings that are intended to be interpreted locale |
|
* independently. |
|
* Examples are programming language identifiers, protocol keys, and HTML |
|
* tags. |
|
* For instance, {@code "title".toUpperCase()} in a Turkish locale |
|
* returns {@code "T\u005Cu0130TLE"}, where '\u005Cu0130' is the |
|
* LATIN CAPITAL LETTER I WITH DOT ABOVE character. |
|
* To obtain correct results for locale insensitive strings, use |
|
* {@code toUpperCase(Locale.ROOT)}. |
|
* <p> |
|
* @return the {@code String}, converted to uppercase. |
|
* @see java.lang.String#toUpperCase(Locale) |
|
*/ |
|
public String toUpperCase() { |
|
return toUpperCase(Locale.getDefault()); |
|
} |
|
/** |
|
* Returns a string whose value is this string, with any leading and trailing |
|
* whitespace removed. |
|
* <p> |
|
* If this {@code String} object represents an empty character |
|
* sequence, or the first and last characters of character sequence |
|
* represented by this {@code String} object both have codes |
|
* greater than {@code '\u005Cu0020'} (the space character), then a |
|
* reference to this {@code String} object is returned. |
|
* <p> |
|
* Otherwise, if there is no character with a code greater than |
|
* {@code '\u005Cu0020'} in the string, then a |
|
* {@code String} object representing an empty string is |
|
* returned. |
|
* <p> |
|
* Otherwise, let <i>k</i> be the index of the first character in the |
|
* string whose code is greater than {@code '\u005Cu0020'}, and let |
|
* <i>m</i> be the index of the last character in the string whose code |
|
* is greater than {@code '\u005Cu0020'}. A {@code String} |
|
* object is returned, representing the substring of this string that |
|
* begins with the character at index <i>k</i> and ends with the |
|
* character at index <i>m</i>-that is, the result of |
|
* {@code this.substring(k, m + 1)}. |
|
* <p> |
|
* This method may be used to trim whitespace (as defined above) from |
|
* the beginning and end of a string. |
|
* |
|
* @return A string whose value is this string, with any leading and trailing white |
|
* space removed, or this string if it has no leading or |
|
* trailing white space. |
|
*/ |
|
public String trim() { |
|
int len = value.length; |
|
int st = 0; |
|
char[] val = value; /* avoid getfield opcode */ |
|
while ((st < len) && (val[st] <= ' ')) { |
|
st++; |
|
} |
|
while ((st < len) && (val[len - 1] <= ' ')) { |
|
len--; |
|
} |
|
return ((st > 0) || (len < value.length)) ? substring(st, len) : this; |
|
} |
|
/** |
|
* This object (which is already a string!) is itself returned. |
|
* |
|
* @return the string itself. |
|
*/ |
|
public String toString() { |
|
return this; |
|
} |
|
/** |
|
* Converts this string to a new character array. |
|
* |
|
* @return a newly allocated character array whose length is the length |
|
* of this string and whose contents are initialized to contain |
|
* the character sequence represented by this string. |
|
*/ |
|
public char[] toCharArray() { |
|
// Cannot use Arrays.copyOf because of class initialization order issues |
|
char result[] = new char[value.length]; |
|
System.arraycopy(value, 0, result, 0, value.length); |
|
return result; |
|
} |
|
/** |
|
* Returns a formatted string using the specified format string and |
|
* arguments. |
|
* |
|
* <p> The locale always used is the one returned by {@link |
|
* java.util.Locale#getDefault() Locale.getDefault()}. |
|
* |
|
* @param format |
|
* A <a href="../util/Formatter.html#syntax">format string</a> |
|
* |
|
* @param args |
|
* Arguments referenced by the format specifiers in the format |
|
* string. If there are more arguments than format specifiers, the |
|
* extra arguments are ignored. The number of arguments is |
|
* variable and may be zero. The maximum number of arguments is |
|
* limited by the maximum dimension of a Java array as defined by |
|
* <cite>The Java™ Virtual Machine Specification</cite>. |
|
* The behaviour on a |
|
* {@code null} argument depends on the <a |
|
* href="../util/Formatter.html#syntax">conversion</a>. |
|
* |
|
* @throws java.util.IllegalFormatException |
|
* If a format string contains an illegal syntax, a format |
|
* specifier that is incompatible with the given arguments, |
|
* insufficient arguments given the format string, or other |
|
* illegal conditions. For specification of all possible |
|
* formatting errors, see the <a |
|
* href="../util/Formatter.html#detail">Details</a> section of the |
|
* formatter class specification. |
|
* |
|
* @return A formatted string |
|
* |
|
* @see java.util.Formatter |
|
* @since 1.5 |
|
*/ |
|
public static String format(String format, Object... args) { |
|
return new Formatter().format(format, args).toString(); |
|
} |
|
/** |
|
* Returns a formatted string using the specified locale, format string, |
|
* and arguments. |
|
* |
|
* @param l |
|
* The {@linkplain java.util.Locale locale} to apply during |
|
* formatting. If {@code l} is {@code null} then no localization |
|
* is applied. |
|
* |
|
* @param format |
|
* A <a href="../util/Formatter.html#syntax">format string</a> |
|
* |
|
* @param args |
|
* Arguments referenced by the format specifiers in the format |
|
* string. If there are more arguments than format specifiers, the |
|
* extra arguments are ignored. The number of arguments is |
|
* variable and may be zero. The maximum number of arguments is |
|
* limited by the maximum dimension of a Java array as defined by |
|
* <cite>The Java™ Virtual Machine Specification</cite>. |
|
* The behaviour on a |
|
* {@code null} argument depends on the |
|
* <a href="../util/Formatter.html#syntax">conversion</a>. |
|
* |
|
* @throws java.util.IllegalFormatException |
|
* If a format string contains an illegal syntax, a format |
|
* specifier that is incompatible with the given arguments, |
|
* insufficient arguments given the format string, or other |
|
* illegal conditions. For specification of all possible |
|
* formatting errors, see the <a |
|
* href="../util/Formatter.html#detail">Details</a> section of the |
|
* formatter class specification |
|
* |
|
* @return A formatted string |
|
* |
|
* @see java.util.Formatter |
|
* @since 1.5 |
|
*/ |
|
public static String format(Locale l, String format, Object... args) { |
|
return new Formatter(l).format(format, args).toString(); |
|
} |
|
/** |
|
* Returns the string representation of the {@code Object} argument. |
|
* |
|
* @param obj an {@code Object}. |
|
* @return if the argument is {@code null}, then a string equal to |
|
* {@code "null"}; otherwise, the value of |
|
* {@code obj.toString()} is returned. |
|
* @see java.lang.Object#toString() |
|
*/ |
|
public static String valueOf(Object obj) { |
|
return (obj == null) ? "null" : obj.toString(); |
|
} |
|
/** |
|
* Returns the string representation of the {@code char} array |
|
* argument. The contents of the character array are copied; subsequent |
|
* modification of the character array does not affect the returned |
|
* string. |
|
* |
|
* @param data the character array. |
|
* @return a {@code String} that contains the characters of the |
|
* character array. |
|
*/ |
|
public static String valueOf(char data[]) { |
|
return new String(data); |
|
} |
|
/** |
|
* Returns the string representation of a specific subarray of the |
|
* {@code char} array argument. |
|
* <p> |
|
* The {@code offset} argument is the index of the first |
|
* character of the subarray. The {@code count} argument |
|
* specifies the length of the subarray. The contents of the subarray |
|
* are copied; subsequent modification of the character array does not |
|
* affect the returned string. |
|
* |
|
* @param data the character array. |
|
* @param offset initial offset of the subarray. |
|
* @param count length of the subarray. |
|
* @return a {@code String} that contains the characters of the |
|
* specified subarray of the character array. |
|
* @exception IndexOutOfBoundsException if {@code offset} is |
|
* negative, or {@code count} is negative, or |
|
* {@code offset+count} is larger than |
|
* {@code data.length}. |
|
*/ |
|
public static String valueOf(char data[], int offset, int count) { |
|
return new String(data, offset, count); |
|
} |
|
/** |
|
* Equivalent to {@link #valueOf(char[], int, int)}. |
|
* |
|
* @param data the character array. |
|
* @param offset initial offset of the subarray. |
|
* @param count length of the subarray. |
|
* @return a {@code String} that contains the characters of the |
|
* specified subarray of the character array. |
|
* @exception IndexOutOfBoundsException if {@code offset} is |
|
* negative, or {@code count} is negative, or |
|
* {@code offset+count} is larger than |
|
* {@code data.length}. |
|
*/ |
|
public static String copyValueOf(char data[], int offset, int count) { |
|
return new String(data, offset, count); |
|
} |
|
/** |
|
* Equivalent to {@link #valueOf(char[])}. |
|
* |
|
* @param data the character array. |
|
* @return a {@code String} that contains the characters of the |
|
* character array. |
|
*/ |
|
public static String copyValueOf(char data[]) { |
|
return new String(data); |
|
} |
|
/** |
|
* Returns the string representation of the {@code boolean} argument. |
|
* |
|
* @param b a {@code boolean}. |
|
* @return if the argument is {@code true}, a string equal to |
|
* {@code "true"} is returned; otherwise, a string equal to |
|
* {@code "false"} is returned. |
|
*/ |
|
public static String valueOf(boolean b) { |
|
return b ? "true" : "false"; |
|
} |
|
/** |
|
* Returns the string representation of the {@code char} |
|
* argument. |
|
* |
|
* @param c a {@code char}. |
|
* @return a string of length {@code 1} containing |
|
* as its single character the argument {@code c}. |
|
*/ |
|
public static String valueOf(char c) { |
|
char data[] = {c}; |
|
return new String(data, true); |
|
} |
|
/** |
|
* Returns the string representation of the {@code int} argument. |
|
* <p> |
|
* The representation is exactly the one returned by the |
|
* {@code Integer.toString} method of one argument. |
|
* |
|
* @param i an {@code int}. |
|
* @return a string representation of the {@code int} argument. |
|
* @see java.lang.Integer#toString(int, int) |
|
*/ |
|
public static String valueOf(int i) { |
|
return Integer.toString(i); |
|
} |
|
/** |
|
* Returns the string representation of the {@code long} argument. |
|
* <p> |
|
* The representation is exactly the one returned by the |
|
* {@code Long.toString} method of one argument. |
|
* |
|
* @param l a {@code long}. |
|
* @return a string representation of the {@code long} argument. |
|
* @see java.lang.Long#toString(long) |
|
*/ |
|
public static String valueOf(long l) { |
|
return Long.toString(l); |
|
} |
|
/** |
|
* Returns the string representation of the {@code float} argument. |
|
* <p> |
|
* The representation is exactly the one returned by the |
|
* {@code Float.toString} method of one argument. |
|
* |
|
* @param f a {@code float}. |
|
* @return a string representation of the {@code float} argument. |
|
* @see java.lang.Float#toString(float) |
|
*/ |
|
public static String valueOf(float f) { |
|
return Float.toString(f); |
|
} |
|
/** |
|
* Returns the string representation of the {@code double} argument. |
|
* <p> |
|
* The representation is exactly the one returned by the |
|
* {@code Double.toString} method of one argument. |
|
* |
|
* @param d a {@code double}. |
|
* @return a string representation of the {@code double} argument. |
|
* @see java.lang.Double#toString(double) |
|
*/ |
|
public static String valueOf(double d) { |
|
return Double.toString(d); |
|
} |
|
/** |
|
* Returns a canonical representation for the string object. |
|
* <p> |
|
* A pool of strings, initially empty, is maintained privately by the |
|
* class {@code String}. |
|
* <p> |
|
* When the intern method is invoked, if the pool already contains a |
|
* string equal to this {@code String} object as determined by |
|
* the {@link #equals(Object)} method, then the string from the pool is |
|
* returned. Otherwise, this {@code String} object is added to the |
|
* pool and a reference to this {@code String} object is returned. |
|
* <p> |
|
* It follows that for any two strings {@code s} and {@code t}, |
|
* {@code s.intern() == t.intern()} is {@code true} |
|
* if and only if {@code s.equals(t)} is {@code true}. |
|
* <p> |
|
* All literal strings and string-valued constant expressions are |
|
* interned. String literals are defined in section 3.10.5 of the |
|
* <cite>The Java™ Language Specification</cite>. |
|
* |
|
* @return a string that has the same contents as this string, but is |
|
* guaranteed to be from a pool of unique strings. |
|
*/ |
|
public native String intern(); |
|
} |