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	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	package org.apache.commons.lang3;

	import java.util.regex.Pattern;

	/**
	* <p>Helpers to process Strings using regular expressions.</p>
	* @see java.util.regex.Pattern
	* @since 3.8
	*/
	public class RegExUtils {

	/**
	* <p>Removes each substring of the text String that matches the given regular expression pattern.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code pattern.matcher(text).replaceAll(StringUtils.EMPTY)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.removeAll(null, *) = null
	* StringUtils.removeAll("any", (Pattern) null) = "any"
	* StringUtils.removeAll("any", Pattern.compile("")) = "any"
	* StringUtils.removeAll("any", Pattern.compile(".*")) = ""
	* StringUtils.removeAll("any", Pattern.compile(".+")) = ""
	* StringUtils.removeAll("abc", Pattern.compile(".?")) = ""
	* StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("<.*>")) = "A\nB"
	* StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("(?s)<.*>")) = "AB"
	* StringUtils.removeAll("A<__>\n<__>B", Pattern.compile("<.*>", Pattern.DOTALL)) = "AB"
	* StringUtils.removeAll("ABCabc123abc", Pattern.compile("[a-z]")) = "ABC123"
	* </pre>
	*
	* @param text text to remove from, may be null
	* @param regex the regular expression to which this string is to be matched
	* @return the text with any removes processed,
	* {@code null} if null String input
	*
	* @see #replaceAll(String, Pattern, String)
	* @see java.util.regex.Matcher#replaceAll(String)
	* @see java.util.regex.Pattern
	*/
	public static String removeAll(final String text, final Pattern regex) {
	return replaceAll(text, regex, StringUtils.EMPTY);
	}

	/**
	* <p>Removes each substring of the text String that matches the given regular expression.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceAll(regex, StringUtils.EMPTY)}</li>
	* <li>{@code Pattern.compile(regex).matcher(text).replaceAll(StringUtils.EMPTY)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <p>Unlike in the {@link #removePattern(String, String)} method, the {@link Pattern#DOTALL} option
	* is NOT automatically added.
	* To use the DOTALL option prepend {@code "(?s)"} to the regex.
	* DOTALL is also known as single-line mode in Perl.</p>
	*
	* <pre>
	* StringUtils.removeAll(null, *) = null
	* StringUtils.removeAll("any", (String) null) = "any"
	* StringUtils.removeAll("any", "") = "any"
	* StringUtils.removeAll("any", ".*") = ""
	* StringUtils.removeAll("any", ".+") = ""
	* StringUtils.removeAll("abc", ".?") = ""
	* StringUtils.removeAll("A<__>\n<__>B", "<.*>") = "A\nB"
	* StringUtils.removeAll("A<__>\n<__>B", "(?s)<.*>") = "AB"
	* StringUtils.removeAll("ABCabc123abc", "[a-z]") = "ABC123"
	* </pre>
	*
	* @param text text to remove from, may be null
	* @param regex the regular expression to which this string is to be matched
	* @return the text with any removes processed,
	* {@code null} if null String input
	*
	* @throws java.util.regex.PatternSyntaxException
	* if the regular expression's syntax is invalid
	*
	* @see #replaceAll(String, String, String)
	* @see #removePattern(String, String)
	* @see String#replaceAll(String, String)
	* @see java.util.regex.Pattern
	* @see java.util.regex.Pattern#DOTALL
	*/
	public static String removeAll(final String text, final String regex) {
	return replaceAll(text, regex, StringUtils.EMPTY);
	}

	/**
	* <p>Removes the first substring of the text string that matches the given regular expression pattern.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code pattern.matcher(text).replaceFirst(StringUtils.EMPTY)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.removeFirst(null, *) = null
	* StringUtils.removeFirst("any", (Pattern) null) = "any"
	* StringUtils.removeFirst("any", Pattern.compile("")) = "any"
	* StringUtils.removeFirst("any", Pattern.compile(".*")) = ""
	* StringUtils.removeFirst("any", Pattern.compile(".+")) = ""
	* StringUtils.removeFirst("abc", Pattern.compile(".?")) = "bc"
	* StringUtils.removeFirst("A<__>\n<__>B", Pattern.compile("<.*>")) = "A\n<__>B"
	* StringUtils.removeFirst("A<__>\n<__>B", Pattern.compile("(?s)<.*>")) = "AB"
	* StringUtils.removeFirst("ABCabc123", Pattern.compile("[a-z]")) = "ABCbc123"
	* StringUtils.removeFirst("ABCabc123abc", Pattern.compile("[a-z]+")) = "ABC123abc"
	* </pre>
	*
	* @param text text to remove from, may be null
	* @param regex the regular expression pattern to which this string is to be matched
	* @return the text with the first replacement processed,
	* {@code null} if null String input
	*
	* @see #replaceFirst(String, Pattern, String)
	* @see java.util.regex.Matcher#replaceFirst(String)
	* @see java.util.regex.Pattern
	*/
	public static String removeFirst(final String text, final Pattern regex) {
	return replaceFirst(text, regex, StringUtils.EMPTY);
	}

	/**
	* <p>Removes the first substring of the text string that matches the given regular expression.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceFirst(regex, StringUtils.EMPTY)}</li>
	* <li>{@code Pattern.compile(regex).matcher(text).replaceFirst(StringUtils.EMPTY)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <p>The {@link Pattern#DOTALL} option is NOT automatically added.
	* To use the DOTALL option prepend {@code "(?s)"} to the regex.
	* DOTALL is also known as single-line mode in Perl.</p>
	*
	* <pre>
	* StringUtils.removeFirst(null, *) = null
	* StringUtils.removeFirst("any", (String) null) = "any"
	* StringUtils.removeFirst("any", "") = "any"
	* StringUtils.removeFirst("any", ".*") = ""
	* StringUtils.removeFirst("any", ".+") = ""
	* StringUtils.removeFirst("abc", ".?") = "bc"
	* StringUtils.removeFirst("A<__>\n<__>B", "<.*>") = "A\n<__>B"
	* StringUtils.removeFirst("A<__>\n<__>B", "(?s)<.*>") = "AB"
	* StringUtils.removeFirst("ABCabc123", "[a-z]") = "ABCbc123"
	* StringUtils.removeFirst("ABCabc123abc", "[a-z]+") = "ABC123abc"
	* </pre>
	*
	* @param text text to remove from, may be null
	* @param regex the regular expression to which this string is to be matched
	* @return the text with the first replacement processed,
	* {@code null} if null String input
	*
	* @throws java.util.regex.PatternSyntaxException
	* if the regular expression's syntax is invalid
	*
	* @see #replaceFirst(String, String, String)
	* @see String#replaceFirst(String, String)
	* @see java.util.regex.Pattern
	* @see java.util.regex.Pattern#DOTALL
	*/
	public static String removeFirst(final String text, final String regex) {
	return replaceFirst(text, regex, StringUtils.EMPTY);
	}

	/**
	* <p>Removes each substring of the source String that matches the given regular expression using the DOTALL option.</p>
	*
	* This call is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceAll("(?s)" + regex, StringUtils.EMPTY)}</li>
	* <li>{@code Pattern.compile(regex, Pattern.DOTALL).matcher(text).replaceAll(StringUtils.EMPTY)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.removePattern(null, *) = null
	* StringUtils.removePattern("any", (String) null) = "any"
	* StringUtils.removePattern("A<__>\n<__>B", "<.*>") = "AB"
	* StringUtils.removePattern("ABCabc123", "[a-z]") = "ABC123"
	* </pre>
	*
	* @param text
	* the source string
	* @param regex
	* the regular expression to which this string is to be matched
	* @return The resulting {@code String}
	* @see #replacePattern(String, String, String)
	* @see String#replaceAll(String, String)
	* @see Pattern#DOTALL
	*/
	public static String removePattern(final String text, final String regex) {
	return replacePattern(text, regex, StringUtils.EMPTY);
	}

	/**
	* <p>Replaces each substring of the text String that matches the given regular expression pattern with the given replacement.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code pattern.matcher(text).replaceAll(replacement)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.replaceAll(null, , ) = null
	* StringUtils.replaceAll("any", (Pattern) null, *) = "any"
	* StringUtils.replaceAll("any", *, null) = "any"
	* StringUtils.replaceAll("", Pattern.compile(""), "zzz") = "zzz"
	* StringUtils.replaceAll("", Pattern.compile(".*"), "zzz") = "zzz"
	* StringUtils.replaceAll("", Pattern.compile(".+"), "zzz") = ""
	* StringUtils.replaceAll("abc", Pattern.compile(""), "ZZ") = "ZZaZZbZZcZZ"
	* StringUtils.replaceAll("<__>\n<__>", Pattern.compile("<.*>"), "z") = "z\nz"
	* StringUtils.replaceAll("<__>\n<__>", Pattern.compile("<.*>", Pattern.DOTALL), "z") = "z"
	* StringUtils.replaceAll("<__>\n<__>", Pattern.compile("(?s)<.*>"), "z") = "z"
	* StringUtils.replaceAll("ABCabc123", Pattern.compile("[a-z]"), "_") = "ABC___123"
	* StringUtils.replaceAll("ABCabc123", Pattern.compile("[^A-Z0-9]+"), "_") = "ABC_123"
	* StringUtils.replaceAll("ABCabc123", Pattern.compile("[^A-Z0-9]+"), "") = "ABC123"
	* StringUtils.replaceAll("Lorem ipsum dolor sit", Pattern.compile("( +)([a-z]+)"), "_$2") = "Lorem_ipsum_dolor_sit"
	* </pre>
	*
	* @param text text to search and replace in, may be null
	* @param regex the regular expression pattern to which this string is to be matched
	* @param replacement the string to be substituted for each match
	* @return the text with any replacements processed,
	* {@code null} if null String input
	*
	* @see java.util.regex.Matcher#replaceAll(String)
	* @see java.util.regex.Pattern
	*/
	public static String replaceAll(final String text, final Pattern regex, final String replacement) {
	if (text == null \|\| regex == null \|\| replacement == null) {
	return text;
	}
	return regex.matcher(text).replaceAll(replacement);
	}

	/**
	* <p>Replaces each substring of the text String that matches the given regular expression
	* with the given replacement.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceAll(regex, replacement)}</li>
	* <li>{@code Pattern.compile(regex).matcher(text).replaceAll(replacement)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <p>Unlike in the {@link #replacePattern(String, String, String)} method, the {@link Pattern#DOTALL} option
	* is NOT automatically added.
	* To use the DOTALL option prepend {@code "(?s)"} to the regex.
	* DOTALL is also known as single-line mode in Perl.</p>
	*
	* <pre>
	* StringUtils.replaceAll(null, , ) = null
	* StringUtils.replaceAll("any", (String) null, *) = "any"
	* StringUtils.replaceAll("any", *, null) = "any"
	* StringUtils.replaceAll("", "", "zzz") = "zzz"
	* StringUtils.replaceAll("", ".*", "zzz") = "zzz"
	* StringUtils.replaceAll("", ".+", "zzz") = ""
	* StringUtils.replaceAll("abc", "", "ZZ") = "ZZaZZbZZcZZ"
	* StringUtils.replaceAll("<__>\n<__>", "<.*>", "z") = "z\nz"
	* StringUtils.replaceAll("<__>\n<__>", "(?s)<.*>", "z") = "z"
	* StringUtils.replaceAll("ABCabc123", "[a-z]", "_") = "ABC___123"
	* StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "_") = "ABC_123"
	* StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "") = "ABC123"
	* StringUtils.replaceAll("Lorem ipsum dolor sit", "( +)([a-z]+)", "_$2") = "Lorem_ipsum_dolor_sit"
	* </pre>
	*
	* @param text text to search and replace in, may be null
	* @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 text with any replacements processed,
	* {@code null} if null String input
	*
	* @throws java.util.regex.PatternSyntaxException
	* if the regular expression's syntax is invalid
	*
	* @see #replacePattern(String, String, String)
	* @see String#replaceAll(String, String)
	* @see java.util.regex.Pattern
	* @see java.util.regex.Pattern#DOTALL
	*/
	public static String replaceAll(final String text, final String regex, final String replacement) {
	if (text == null \|\| regex == null \|\| replacement == null) {
	return text;
	}
	return text.replaceAll(regex, replacement);
	}

	/**
	* <p>Replaces the first substring of the text string that matches the given regular expression pattern
	* with the given replacement.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code pattern.matcher(text).replaceFirst(replacement)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.replaceFirst(null, , ) = null
	* StringUtils.replaceFirst("any", (Pattern) null, *) = "any"
	* StringUtils.replaceFirst("any", *, null) = "any"
	* StringUtils.replaceFirst("", Pattern.compile(""), "zzz") = "zzz"
	* StringUtils.replaceFirst("", Pattern.compile(".*"), "zzz") = "zzz"
	* StringUtils.replaceFirst("", Pattern.compile(".+"), "zzz") = ""
	* StringUtils.replaceFirst("abc", Pattern.compile(""), "ZZ") = "ZZabc"
	* StringUtils.replaceFirst("<__>\n<__>", Pattern.compile("<.*>"), "z") = "z\n<__>"
	* StringUtils.replaceFirst("<__>\n<__>", Pattern.compile("(?s)<.*>"), "z") = "z"
	* StringUtils.replaceFirst("ABCabc123", Pattern.compile("[a-z]"), "_") = "ABC_bc123"
	* StringUtils.replaceFirst("ABCabc123abc", Pattern.compile("[^A-Z0-9]+"), "_") = "ABC_123abc"
	* StringUtils.replaceFirst("ABCabc123abc", Pattern.compile("[^A-Z0-9]+"), "") = "ABC123abc"
	* StringUtils.replaceFirst("Lorem ipsum dolor sit", Pattern.compile("( +)([a-z]+)"), "_$2") = "Lorem_ipsum dolor sit"
	* </pre>
	*
	* @param text text to search and replace in, may be null
	* @param regex the regular expression pattern to which this string is to be matched
	* @param replacement the string to be substituted for the first match
	* @return the text with the first replacement processed,
	* {@code null} if null String input
	*
	* @see java.util.regex.Matcher#replaceFirst(String)
	* @see java.util.regex.Pattern
	*/
	public static String replaceFirst(final String text, final Pattern regex, final String replacement) {
	if (text == null \|\| regex == null\|\| replacement == null ) {
	return text;
	}
	return regex.matcher(text).replaceFirst(replacement);
	}

	/**
	* <p>Replaces the first substring of the text string that matches the given regular expression
	* with the given replacement.</p>
	*
	* This method is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceFirst(regex, replacement)}</li>
	* <li>{@code Pattern.compile(regex).matcher(text).replaceFirst(replacement)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <p>The {@link Pattern#DOTALL} option is NOT automatically added.
	* To use the DOTALL option prepend {@code "(?s)"} to the regex.
	* DOTALL is also known as single-line mode in Perl.</p>
	*
	* <pre>
	* StringUtils.replaceFirst(null, , ) = null
	* StringUtils.replaceFirst("any", (String) null, *) = "any"
	* StringUtils.replaceFirst("any", *, null) = "any"
	* StringUtils.replaceFirst("", "", "zzz") = "zzz"
	* StringUtils.replaceFirst("", ".*", "zzz") = "zzz"
	* StringUtils.replaceFirst("", ".+", "zzz") = ""
	* StringUtils.replaceFirst("abc", "", "ZZ") = "ZZabc"
	* StringUtils.replaceFirst("<__>\n<__>", "<.*>", "z") = "z\n<__>"
	* StringUtils.replaceFirst("<__>\n<__>", "(?s)<.*>", "z") = "z"
	* StringUtils.replaceFirst("ABCabc123", "[a-z]", "_") = "ABC_bc123"
	* StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "_") = "ABC_123abc"
	* StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "") = "ABC123abc"
	* StringUtils.replaceFirst("Lorem ipsum dolor sit", "( +)([a-z]+)", "_$2") = "Lorem_ipsum dolor sit"
	* </pre>
	*
	* @param text text to search and replace in, may be null
	* @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 text with the first replacement processed,
	* {@code null} if null String input
	*
	* @throws java.util.regex.PatternSyntaxException
	* if the regular expression's syntax is invalid
	*
	* @see String#replaceFirst(String, String)
	* @see java.util.regex.Pattern
	* @see java.util.regex.Pattern#DOTALL
	*/
	public static String replaceFirst(final String text, final String regex, final String replacement) {
	if (text == null \|\| regex == null\|\| replacement == null ) {
	return text;
	}
	return text.replaceFirst(regex, replacement);
	}

	/**
	* <p>Replaces each substring of the source String that matches the given regular expression with the given
	* replacement using the {@link Pattern#DOTALL} option. DOTALL is also known as single-line mode in Perl.</p>
	*
	* This call is a {@code null} safe equivalent to:
	* <ul>
	* <li>{@code text.replaceAll("(?s)" + regex, replacement)}</li>
	* <li>{@code Pattern.compile(regex, Pattern.DOTALL).matcher(text).replaceAll(replacement)}</li>
	* </ul>
	*
	* <p>A {@code null} reference passed to this method is a no-op.</p>
	*
	* <pre>
	* StringUtils.replacePattern(null, , ) = null
	* StringUtils.replacePattern("any", (String) null, *) = "any"
	* StringUtils.replacePattern("any", *, null) = "any"
	* StringUtils.replacePattern("", "", "zzz") = "zzz"
	* StringUtils.replacePattern("", ".*", "zzz") = "zzz"
	* StringUtils.replacePattern("", ".+", "zzz") = ""
	* StringUtils.replacePattern("<__>\n<__>", "<.*>", "z") = "z"
	* StringUtils.replacePattern("ABCabc123", "[a-z]", "_") = "ABC___123"
	* StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "_") = "ABC_123"
	* StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "") = "ABC123"
	* StringUtils.replacePattern("Lorem ipsum dolor sit", "( +)([a-z]+)", "_$2") = "Lorem_ipsum_dolor_sit"
	* </pre>
	*
	* @param text
	* the source string
	* @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}
	* @see #replaceAll(String, String, String)
	* @see String#replaceAll(String, String)
	* @see Pattern#DOTALL
	*/
	public static String replacePattern(final String text, final String regex, final String replacement) {
	if (text == null \|\| regex == null \|\| replacement == null) {
	return text;
	}
	return Pattern.compile(regex, Pattern.DOTALL).matcher(text).replaceAll(replacement);
	}

	}

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