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	/*
	* Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.lang;

	/**
	* The Boolean class wraps a value of the primitive type
	* {@code boolean} in an object. An object of type
	* {@code Boolean} contains a single field whose type is
	* {@code boolean}.
	* <p>
	* In addition, this class provides many methods for
	* converting a {@code boolean} to a {@code String} and a
	* {@code String} to a {@code boolean}, as well as other
	* constants and methods useful when dealing with a
	* {@code boolean}.
	*
	* @author Arthur van Hoff
	* @since JDK1.0
	*/
	public final class Boolean implements java.io.Serializable,
	Comparable<Boolean>
	{
	/**
	* The {@code Boolean} object corresponding to the primitive
	* value {@code true}.
	*/
	public static final Boolean TRUE = new Boolean(true);

	/**
	* The {@code Boolean} object corresponding to the primitive
	* value {@code false}.
	*/
	public static final Boolean FALSE = new Boolean(false);

	/**
	* The Class object representing the primitive type boolean.
	*
	* @since JDK1.1
	*/
	@SuppressWarnings("unchecked")
	public static final Class<Boolean> TYPE = (Class<Boolean>) Class.getPrimitiveClass("boolean");

	/**
	* The value of the Boolean.
	*
	* @serial
	*/
	private final boolean value;

	/** use serialVersionUID from JDK 1.0.2 for interoperability */
	private static final long serialVersionUID = -3665804199014368530L;

	/**
	* Allocates a {@code Boolean} object representing the
	* {@code value} argument.
	*
	* <p><b>Note: It is rarely appropriate to use this constructor.
	* Unless a <i>new</i> instance is required, the static factory
	* {@link #valueOf(boolean)} is generally a better choice. It is
	* likely to yield significantly better space and time performance.</b>
	*
	* @param value the value of the {@code Boolean}.
	*/
	public Boolean(boolean value) {
	this.value = value;
	}

	/**
	* Allocates a {@code Boolean} object representing the value
	* {@code true} if the string argument is not {@code null}
	* and is equal, ignoring case, to the string {@code "true"}.
	* Otherwise, allocate a {@code Boolean} object representing the
	* value {@code false}. Examples:<p>
	* {@code new Boolean("True")} produces a {@code Boolean} object
	* that represents {@code true}.<br>
	* {@code new Boolean("yes")} produces a {@code Boolean} object
	* that represents {@code false}.
	*
	* @param s the string to be converted to a {@code Boolean}.
	*/
	public Boolean(String s) {
	this(parseBoolean(s));
	}

	/**
	* Parses the string argument as a boolean. The {@code boolean}
	* returned represents the value {@code true} if the string argument
	* is not {@code null} and is equal, ignoring case, to the string
	* {@code "true"}. <p>
	* Example: {@code Boolean.parseBoolean("True")} returns {@code true}.<br>
	* Example: {@code Boolean.parseBoolean("yes")} returns {@code false}.
	*
	* @param s the {@code String} containing the boolean
	* representation to be parsed
	* @return the boolean represented by the string argument
	* @since 1.5
	*/
	public static boolean parseBoolean(String s) {
	return ((s != null) && s.equalsIgnoreCase("true"));
	}

	/**
	* Returns the value of this {@code Boolean} object as a boolean
	* primitive.
	*
	* @return the primitive {@code boolean} value of this object.
	*/
	public boolean booleanValue() {
	return value;
	}

	/**
	* Returns a {@code Boolean} instance representing the specified
	* {@code boolean} value. If the specified {@code boolean} value
	* is {@code true}, this method returns {@code Boolean.TRUE};
	* if it is {@code false}, this method returns {@code Boolean.FALSE}.
	* If a new {@code Boolean} instance is not required, this method
	* should generally be used in preference to the constructor
	* {@link #Boolean(boolean)}, as this method is likely to yield
	* significantly better space and time performance.
	*
	* @param b a boolean value.
	* @return a {@code Boolean} instance representing {@code b}.
	* @since 1.4
	*/
	public static Boolean valueOf(boolean b) {
	return (b ? TRUE : FALSE);
	}

	/**
	* Returns a {@code Boolean} with a value represented by the
	* specified string. The {@code Boolean} returned represents a
	* true value if the string argument is not {@code null}
	* and is equal, ignoring case, to the string {@code "true"}.
	*
	* @param s a string.
	* @return the {@code Boolean} value represented by the string.
	*/
	public static Boolean valueOf(String s) {
	return parseBoolean(s) ? TRUE : FALSE;
	}

	/**
	* Returns a {@code String} object representing the specified
	* boolean. If the specified boolean is {@code true}, then
	* the string {@code "true"} will be returned, otherwise the
	* string {@code "false"} will be returned.
	*
	* @param b the boolean to be converted
	* @return the string representation of the specified {@code boolean}
	* @since 1.4
	*/
	public static String toString(boolean b) {
	return b ? "true" : "false";
	}

	/**
	* Returns a {@code String} object representing this Boolean's
	* value. If this object represents the value {@code true},
	* a string equal to {@code "true"} is returned. Otherwise, a
	* string equal to {@code "false"} is returned.
	*
	* @return a string representation of this object.
	*/
	public String toString() {
	return value ? "true" : "false";
	}

	/**
	* Returns a hash code for this {@code Boolean} object.
	*
	* @return the integer {@code 1231} if this object represents
	* {@code true}; returns the integer {@code 1237} if this
	* object represents {@code false}.
	*/
	@Override
	public int hashCode() {
	return Boolean.hashCode(value);
	}

	/**
	* Returns a hash code for a {@code boolean} value; compatible with
	* {@code Boolean.hashCode()}.
	*
	* @param value the value to hash
	* @return a hash code value for a {@code boolean} value.
	* @since 1.8
	*/
	public static int hashCode(boolean value) {
	return value ? 1231 : 1237;
	}

	/**
	* Returns {@code true} if and only if the argument is not
	* {@code null} and is a {@code Boolean} object that
	* represents the same {@code boolean} value as this object.
	*
	* @param obj the object to compare with.
	* @return {@code true} if the Boolean objects represent the
	* same value; {@code false} otherwise.
	*/
	public boolean equals(Object obj) {
	if (obj instanceof Boolean) {
	return value == ((Boolean)obj).booleanValue();
	}
	return false;
	}

	/**
	* Returns {@code true} if and only if the system property
	* named by the argument exists and is equal to the string
	* {@code "true"}. (Beginning with version 1.0.2 of the
	* Java<small><sup>TM</sup></small> platform, the test of
	* this string is case insensitive.) A system property is accessible
	* through {@code getProperty}, a method defined by the
	* {@code System} class.
	* <p>
	* If there is no property with the specified name, or if the specified
	* name is empty or null, then {@code false} is returned.
	*
	* @param name the system property name.
	* @return the {@code boolean} value of the system property.
	* @throws SecurityException for the same reasons as
	* {@link System#getProperty(String) System.getProperty}
	* @see java.lang.System#getProperty(java.lang.String)
	* @see java.lang.System#getProperty(java.lang.String, java.lang.String)
	*/
	public static boolean getBoolean(String name) {
	boolean result = false;
	try {
	result = parseBoolean(System.getProperty(name));
	} catch (IllegalArgumentException \| NullPointerException e) {
	}
	return result;
	}

	/**
	* Compares this {@code Boolean} instance with another.
	*
	* @param b the {@code Boolean} instance to be compared
	* @return zero if this object represents the same boolean value as the
	* argument; a positive value if this object represents true
	* and the argument represents false; and a negative value if
	* this object represents false and the argument represents true
	* @throws NullPointerException if the argument is {@code null}
	* @see Comparable
	* @since 1.5
	*/
	public int compareTo(Boolean b) {
	return compare(this.value, b.value);
	}

	/**
	* Compares two {@code boolean} values.
	* The value returned is identical to what would be returned by:
	* <pre>
	* Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
	* </pre>
	*
	* @param x the first {@code boolean} to compare
	* @param y the second {@code boolean} to compare
	* @return the value {@code 0} if {@code x == y};
	* a value less than {@code 0} if {@code !x && y}; and
	* a value greater than {@code 0} if {@code x && !y}
	* @since 1.7
	*/
	public static int compare(boolean x, boolean y) {
	return (x == y) ? 0 : (x ? 1 : -1);
	}

	/**
	* Returns the result of applying the logical AND operator to the
	* specified {@code boolean} operands.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the logical AND of {@code a} and {@code b}
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static boolean logicalAnd(boolean a, boolean b) {
	return a && b;
	}

	/**
	* Returns the result of applying the logical OR operator to the
	* specified {@code boolean} operands.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the logical OR of {@code a} and {@code b}
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static boolean logicalOr(boolean a, boolean b) {
	return a \|\| b;
	}

	/**
	* Returns the result of applying the logical XOR operator to the
	* specified {@code boolean} operands.
	*
	* @param a the first operand
	* @param b the second operand
	* @return the logical XOR of {@code a} and {@code b}
	* @see java.util.function.BinaryOperator
	* @since 1.8
	*/
	public static boolean logicalXor(boolean a, boolean b) {
	return a ^ b;
	}
	}

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