StringEscapeUtils.java
/*
* 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
*
* https://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.io.IOException;
import java.io.Writer;
import org.apache.commons.lang3.text.translate.AggregateTranslator;
import org.apache.commons.lang3.text.translate.CharSequenceTranslator;
import org.apache.commons.lang3.text.translate.EntityArrays;
import org.apache.commons.lang3.text.translate.JavaUnicodeEscaper;
import org.apache.commons.lang3.text.translate.LookupTranslator;
import org.apache.commons.lang3.text.translate.NumericEntityEscaper;
import org.apache.commons.lang3.text.translate.NumericEntityUnescaper;
import org.apache.commons.lang3.text.translate.OctalUnescaper;
import org.apache.commons.lang3.text.translate.UnicodeUnescaper;
import org.apache.commons.lang3.text.translate.UnicodeUnpairedSurrogateRemover;
/**
* Escapes and unescapes {@link String}s for
* Java, Java Script, HTML and XML.
*
* <p>#ThreadSafe#</p>
* @since 2.0
* @deprecated As of 3.6, use Apache Commons Text
* <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/StringEscapeUtils.html">
* StringEscapeUtils</a> instead
*/
@Deprecated
public class StringEscapeUtils {
/* ESCAPE TRANSLATORS */
private static final class CsvEscaper extends CharSequenceTranslator {
private static final char CSV_DELIMITER = ',';
private static final char CSV_QUOTE = '"';
private static final String CSV_QUOTE_STR = String.valueOf(CSV_QUOTE);
private static final char[] CSV_SEARCH_CHARS = { CSV_DELIMITER, CSV_QUOTE, CharUtils.CR, CharUtils.LF };
@Override
public int translate(final CharSequence input, final int index, final Writer out) throws IOException {
if (index != 0) {
throw new IllegalStateException("CsvEscaper should never reach the [1] index");
}
if (StringUtils.containsNone(input.toString(), CSV_SEARCH_CHARS)) {
out.write(input.toString());
} else {
out.write(CSV_QUOTE);
out.write(Strings.CS.replace(input.toString(), CSV_QUOTE_STR, CSV_QUOTE_STR + CSV_QUOTE_STR));
out.write(CSV_QUOTE);
}
return Character.codePointCount(input, 0, input.length());
}
}
private static final class CsvUnescaper extends CharSequenceTranslator {
private static final char CSV_DELIMITER = ',';
private static final char CSV_QUOTE = '"';
private static final String CSV_QUOTE_STR = String.valueOf(CSV_QUOTE);
private static final char[] CSV_SEARCH_CHARS = {CSV_DELIMITER, CSV_QUOTE, CharUtils.CR, CharUtils.LF};
@Override
public int translate(final CharSequence input, final int index, final Writer out) throws IOException {
if (index != 0) {
throw new IllegalStateException("CsvUnescaper should never reach the [1] index");
}
if (input.charAt(0) != CSV_QUOTE || input.charAt(input.length() - 1) != CSV_QUOTE) {
out.write(input.toString());
return Character.codePointCount(input, 0, input.length());
}
// strip quotes
final String quoteless = input.subSequence(1, input.length() - 1).toString();
if (StringUtils.containsAny(quoteless, CSV_SEARCH_CHARS)) {
// deal with escaped quotes; ie) ""
out.write(Strings.CS.replace(quoteless, CSV_QUOTE_STR + CSV_QUOTE_STR, CSV_QUOTE_STR));
} else {
out.write(input.toString());
}
return Character.codePointCount(input, 0, input.length());
}
}
/**
* Translator object for escaping Java.
*
* While {@link #escapeJava(String)} is the expected method of use, this
* object allows the Java escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator ESCAPE_JAVA =
new LookupTranslator(
new String[][] {
{"\"", "\\\""},
{"\\", "\\\\"},
}).with(
new LookupTranslator(EntityArrays.JAVA_CTRL_CHARS_ESCAPE())
).with(
JavaUnicodeEscaper.outsideOf(32, 0x7f)
);
/**
* Translator object for escaping EcmaScript/JavaScript.
*
* While {@link #escapeEcmaScript(String)} is the expected method of use, this
* object allows the EcmaScript escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator ESCAPE_ECMASCRIPT =
new AggregateTranslator(
new LookupTranslator(
new String[][] {
{"'", "\\'"},
{"\"", "\\\""},
{"\\", "\\\\"},
{"/", "\\/"}
}),
new LookupTranslator(EntityArrays.JAVA_CTRL_CHARS_ESCAPE()),
JavaUnicodeEscaper.outsideOf(32, 0x7f)
);
/**
* Translator object for escaping Json.
*
* While {@link #escapeJson(String)} is the expected method of use, this
* object allows the Json escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.2
*/
public static final CharSequenceTranslator ESCAPE_JSON =
new AggregateTranslator(
new LookupTranslator(
new String[][] {
{"\"", "\\\""},
{"\\", "\\\\"},
{"/", "\\/"}
}),
new LookupTranslator(EntityArrays.JAVA_CTRL_CHARS_ESCAPE()),
JavaUnicodeEscaper.outsideOf(32, 0x7f)
);
/**
* Translator object for escaping XML.
*
* While {@link #escapeXml(String)} is the expected method of use, this
* object allows the XML escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
* @deprecated use {@link #ESCAPE_XML10} or {@link #ESCAPE_XML11} instead.
*/
@Deprecated
public static final CharSequenceTranslator ESCAPE_XML =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_ESCAPE()),
new LookupTranslator(EntityArrays.APOS_ESCAPE())
);
/**
* Translator object for escaping XML 1.0.
*
* While {@link #escapeXml10(String)} is the expected method of use, this
* object allows the XML escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.3
*/
public static final CharSequenceTranslator ESCAPE_XML10 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_ESCAPE()),
new LookupTranslator(EntityArrays.APOS_ESCAPE()),
new LookupTranslator(
new String[][] {
{ "\u0000", StringUtils.EMPTY },
{ "\u0001", StringUtils.EMPTY },
{ "\u0002", StringUtils.EMPTY },
{ "\u0003", StringUtils.EMPTY },
{ "\u0004", StringUtils.EMPTY },
{ "\u0005", StringUtils.EMPTY },
{ "\u0006", StringUtils.EMPTY },
{ "\u0007", StringUtils.EMPTY },
{ "\u0008", StringUtils.EMPTY },
{ "\u000b", StringUtils.EMPTY },
{ "\u000c", StringUtils.EMPTY },
{ "\u000e", StringUtils.EMPTY },
{ "\u000f", StringUtils.EMPTY },
{ "\u0010", StringUtils.EMPTY },
{ "\u0011", StringUtils.EMPTY },
{ "\u0012", StringUtils.EMPTY },
{ "\u0013", StringUtils.EMPTY },
{ "\u0014", StringUtils.EMPTY },
{ "\u0015", StringUtils.EMPTY },
{ "\u0016", StringUtils.EMPTY },
{ "\u0017", StringUtils.EMPTY },
{ "\u0018", StringUtils.EMPTY },
{ "\u0019", StringUtils.EMPTY },
{ "\u001a", StringUtils.EMPTY },
{ "\u001b", StringUtils.EMPTY },
{ "\u001c", StringUtils.EMPTY },
{ "\u001d", StringUtils.EMPTY },
{ "\u001e", StringUtils.EMPTY },
{ "\u001f", StringUtils.EMPTY },
{ "\ufffe", StringUtils.EMPTY },
{ "\uffff", StringUtils.EMPTY }
}),
NumericEntityEscaper.between(0x7f, 0x84),
NumericEntityEscaper.between(0x86, 0x9f),
new UnicodeUnpairedSurrogateRemover()
);
/**
* Translator object for escaping XML 1.1.
*
* While {@link #escapeXml11(String)} is the expected method of use, this
* object allows the XML escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.3
*/
public static final CharSequenceTranslator ESCAPE_XML11 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_ESCAPE()),
new LookupTranslator(EntityArrays.APOS_ESCAPE()),
new LookupTranslator(
new String[][] {
{ "\u0000", StringUtils.EMPTY },
{ "\u000b", "" },
{ "\u000c", "" },
{ "\ufffe", StringUtils.EMPTY },
{ "\uffff", StringUtils.EMPTY }
}),
NumericEntityEscaper.between(0x1, 0x8),
NumericEntityEscaper.between(0xe, 0x1f),
NumericEntityEscaper.between(0x7f, 0x84),
NumericEntityEscaper.between(0x86, 0x9f),
new UnicodeUnpairedSurrogateRemover()
);
/**
* Translator object for escaping HTML version 3.0.
*
* While {@link #escapeHtml3(String)} is the expected method of use, this
* object allows the HTML escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator ESCAPE_HTML3 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_ESCAPE()),
new LookupTranslator(EntityArrays.ISO8859_1_ESCAPE())
);
/**
* Translator object for escaping HTML version 4.0.
*
* While {@link #escapeHtml4(String)} is the expected method of use, this
* object allows the HTML escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator ESCAPE_HTML4 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_ESCAPE()),
new LookupTranslator(EntityArrays.ISO8859_1_ESCAPE()),
new LookupTranslator(EntityArrays.HTML40_EXTENDED_ESCAPE())
);
/* UNESCAPE TRANSLATORS */
/**
* Translator object for escaping individual Comma Separated Values.
*
* While {@link #escapeCsv(String)} is the expected method of use, this
* object allows the CSV escaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator ESCAPE_CSV = new CsvEscaper();
/**
* Translator object for unescaping escaped Java.
*
* While {@link #unescapeJava(String)} is the expected method of use, this
* object allows the Java unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
// TODO: throw "illegal character: \92" as an Exception if a \ on the end of the Java (as per the compiler)?
public static final CharSequenceTranslator UNESCAPE_JAVA =
new AggregateTranslator(
new OctalUnescaper(), // .between('\1', '\377'),
new UnicodeUnescaper(),
new LookupTranslator(EntityArrays.JAVA_CTRL_CHARS_UNESCAPE()),
new LookupTranslator(
new String[][] {
{"\\\\", "\\"},
{"\\\"", "\""},
{"\\'", "'"},
{"\\", ""}
})
);
/**
* Translator object for unescaping escaped EcmaScript.
*
* While {@link #unescapeEcmaScript(String)} is the expected method of use, this
* object allows the EcmaScript unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator UNESCAPE_ECMASCRIPT = UNESCAPE_JAVA;
/**
* Translator object for unescaping escaped Json.
*
* While {@link #unescapeJson(String)} is the expected method of use, this
* object allows the Json unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.2
*/
public static final CharSequenceTranslator UNESCAPE_JSON = UNESCAPE_JAVA;
/**
* Translator object for unescaping escaped HTML 3.0.
*
* While {@link #unescapeHtml3(String)} is the expected method of use, this
* object allows the HTML unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator UNESCAPE_HTML3 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_UNESCAPE()),
new LookupTranslator(EntityArrays.ISO8859_1_UNESCAPE()),
new NumericEntityUnescaper()
);
/**
* Translator object for unescaping escaped HTML 4.0.
*
* While {@link #unescapeHtml4(String)} is the expected method of use, this
* object allows the HTML unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator UNESCAPE_HTML4 =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_UNESCAPE()),
new LookupTranslator(EntityArrays.ISO8859_1_UNESCAPE()),
new LookupTranslator(EntityArrays.HTML40_EXTENDED_UNESCAPE()),
new NumericEntityUnescaper()
);
/**
* Translator object for unescaping escaped XML.
*
* While {@link #unescapeXml(String)} is the expected method of use, this
* object allows the XML unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator UNESCAPE_XML =
new AggregateTranslator(
new LookupTranslator(EntityArrays.BASIC_UNESCAPE()),
new LookupTranslator(EntityArrays.APOS_UNESCAPE()),
new NumericEntityUnescaper()
);
/**
* Translator object for unescaping escaped Comma Separated Value entries.
*
* While {@link #unescapeCsv(String)} is the expected method of use, this
* object allows the CSV unescaping functionality to be used
* as the foundation for a custom translator.
*
* @since 3.0
*/
public static final CharSequenceTranslator UNESCAPE_CSV = new CsvUnescaper();
/* Helper functions */
/**
* Returns a {@link String} value for a CSV column enclosed in double quotes,
* if required.
*
* <p>If the value contains a comma, newline or double quote, then the
* String value is returned enclosed in double quotes.</p>
*
* <p>Any double quote characters in the value are escaped with another double quote.</p>
*
* <p>If the value does not contain a comma, newline or double quote, then the
* String value is returned unchanged.</p>
*
* see <a href="https://en.wikipedia.org/wiki/Comma-separated_values">Wikipedia</a> and
* <a href="https://datatracker.ietf.org/doc/html/rfc4180">RFC 4180</a>.
*
* @param input the input CSV column String, may be null
* @return the input String, enclosed in double quotes if the value contains a comma,
* newline or double quote, {@code null} if null string input
* @since 2.4
*/
public static final String escapeCsv(final String input) {
return ESCAPE_CSV.translate(input);
}
/**
* Escapes the characters in a {@link String} using EcmaScript String rules.
* <p>Escapes any values it finds into their EcmaScript String form.
* Deals correctly with quotes and control-chars (tab, backslash, cr, ff, etc.) </p>
*
* <p>So a tab becomes the characters {@code '\\'} and
* {@code 't'}.</p>
*
* <p>The only difference between Java strings and EcmaScript strings
* is that in EcmaScript, a single quote and forward-slash (/) are escaped.</p>
*
* <p>Note that EcmaScript is best known by the JavaScript and ActionScript dialects.</p>
*
* <p>Example:</p>
* <pre>
* input string: He didn't say, "Stop!"
* output string: He didn\'t say, \"Stop!\"
* </pre>
*
* @param input String to escape values in, may be null
* @return String with escaped values, {@code null} if null string input
* @since 3.0
*/
public static final String escapeEcmaScript(final String input) {
return ESCAPE_ECMASCRIPT.translate(input);
}
/**
* Escapes the characters in a {@link String} using HTML entities.
* <p>Supports only the HTML 3.0 entities.</p>
*
* @param input the {@link String} to escape, may be null
* @return a new escaped {@link String}, {@code null} if null string input
* @since 3.0
*/
public static final String escapeHtml3(final String input) {
return ESCAPE_HTML3.translate(input);
}
/**
* Escapes the characters in a {@link String} using HTML entities.
*
* <p>
* For example:
* </p>
* <p>{@code "bread" & "butter"}</p>
* becomes:
* <p>
* {@code &quot;bread&quot; &amp; &quot;butter&quot;}.
* </p>
*
* <p>Supports all known HTML 4.0 entities, including funky accents.
* Note that the commonly used apostrophe escape character (&apos;)
* is not a legal entity and so is not supported).</p>
*
* @param input the {@link String} to escape, may be null
* @return a new escaped {@link String}, {@code null} if null string input
* @see <a href="https://web.archive.org/web/20060225074150/https://hotwired.lycos.com/webmonkey/reference/special_characters/">ISO Entities</a>
* @see <a href="https://www.w3.org/TR/REC-html32#latin1">HTML 3.2 Character Entities for ISO Latin-1</a>
* @see <a href="https://www.w3.org/TR/REC-html40/sgml/entities.html">HTML 4.0 Character entity references</a>
* @see <a href="https://www.w3.org/TR/html401/charset.html#h-5.3">HTML 4.01 Character References</a>
* @see <a href="https://www.w3.org/TR/html401/charset.html#code-position">HTML 4.01 Code positions</a>
* @since 3.0
*/
public static final String escapeHtml4(final String input) {
return ESCAPE_HTML4.translate(input);
}
/**
* Escapes the characters in a {@link String} using Java String rules.
*
* <p>Deals correctly with quotes and control-chars (tab, backslash, cr, ff, etc.) </p>
*
* <p>So a tab becomes the characters {@code '\\'} and
* {@code 't'}.</p>
*
* <p>The only difference between Java strings and JavaScript strings
* is that in JavaScript, a single quote and forward-slash (/) are escaped.</p>
*
* <p>Example:</p>
* <pre>
* input string: He didn't say, "Stop!"
* output string: He didn't say, \"Stop!\"
* </pre>
*
* @param input String to escape values in, may be null
* @return String with escaped values, {@code null} if null string input
*/
public static final String escapeJava(final String input) {
return ESCAPE_JAVA.translate(input);
}
/**
* Escapes the characters in a {@link String} using Json String rules.
* <p>Escapes any values it finds into their Json String form.
* Deals correctly with quotes and control-chars (tab, backslash, cr, ff, etc.) </p>
*
* <p>So a tab becomes the characters {@code '\\'} and
* {@code 't'}.</p>
*
* <p>The only difference between Java strings and Json strings
* is that in Json, forward-slash (/) is escaped.</p>
*
* <p>See https://www.ietf.org/rfc/rfc4627.txt for further details.</p>
*
* <p>Example:</p>
* <pre>
* input string: He didn't say, "Stop!"
* output string: He didn't say, \"Stop!\"
* </pre>
*
* @param input String to escape values in, may be null
* @return String with escaped values, {@code null} if null string input
* @since 3.2
*/
public static final String escapeJson(final String input) {
return ESCAPE_JSON.translate(input);
}
/**
* Escapes the characters in a {@link String} using XML entities.
*
* <p>For example: {@code "bread" & "butter"} =>
* {@code "bread" & "butter"}.
* </p>
*
* <p>Supports only the five basic XML entities (gt, lt, quot, amp, apos).
* Does not support DTDs or external entities.</p>
*
* <p>Note that Unicode characters greater than 0x7f are as of 3.0, no longer
* escaped. If you still wish this functionality, you can achieve it
* via the following:
* {@code StringEscapeUtils.ESCAPE_XML.with( NumericEntityEscaper.between(0x7f, Integer.MAX_VALUE));}</p>
*
* @param input the {@link String} to escape, may be null
* @return a new escaped {@link String}, {@code null} if null string input
* @see #unescapeXml(String)
* @deprecated use {@link #escapeXml10(java.lang.String)} or {@link #escapeXml11(java.lang.String)} instead.
*/
@Deprecated
public static final String escapeXml(final String input) {
return ESCAPE_XML.translate(input);
}
/**
* Escapes the characters in a {@link String} using XML entities.
* <p>
* For example:
* </p>
*
* <pre>{@code
* "bread" & "butter"
* }</pre>
* <p>
* converts to:
* </p>
*
* <pre>
* {@code
* "bread" & "butter"
* }
* </pre>
*
* <p>
* Note that XML 1.0 is a text-only format: it cannot represent control characters or unpaired Unicode surrogate code points, even after escaping. The
* method {@code escapeXml10} will remove characters that do not fit in the following ranges:
* </p>
*
* <p>
* {@code #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]}
* </p>
*
* <p>
* Though not strictly necessary, {@code escapeXml10} will escape characters in the following ranges:
* </p>
*
* <p>
* {@code [#x7F-#x84] | [#x86-#x9F]}
* </p>
*
* <p>
* The returned string can be inserted into a valid XML 1.0 or XML 1.1 document. If you want to allow more non-text characters in an XML 1.1 document, use
* {@link #escapeXml11(String)}.
* </p>
*
* @param input the {@link String} to escape, may be null
* @return a new escaped {@link String}, {@code null} if null string input
* @see #unescapeXml(String)
* @since 3.3
*/
public static String escapeXml10(final String input) {
return ESCAPE_XML10.translate(input);
}
/**
* Escapes the characters in a {@link String} using XML entities.
*
* <p>For example: {@code "bread" & "butter"} =>
* {@code "bread" & "butter"}.
* </p>
*
* <p>XML 1.1 can represent certain control characters, but it cannot represent
* the null byte or unpaired Unicode surrogate code points, even after escaping.
* {@code escapeXml11} will remove characters that do not fit in the following
* ranges:</p>
*
* <p>{@code [#x1-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]}</p>
*
* <p>{@code escapeXml11} will escape characters in the following ranges:</p>
*
* <p>{@code [#x1-#x8] | [#xB-#xC] | [#xE-#x1F] | [#x7F-#x84] | [#x86-#x9F]}</p>
*
* <p>The returned string can be inserted into a valid XML 1.1 document. Do not
* use it for XML 1.0 documents.</p>
*
* @param input the {@link String} to escape, may be null
* @return a new escaped {@link String}, {@code null} if null string input
* @see #unescapeXml(String)
* @since 3.3
*/
public static String escapeXml11(final String input) {
return ESCAPE_XML11.translate(input);
}
/**
* Returns a {@link String} value for an unescaped CSV column.
*
* <p>If the value is enclosed in double quotes, and contains a comma, newline
* or double quote, then quotes are removed.
* </p>
*
* <p>Any double quote escaped characters (a pair of double quotes) are unescaped
* to just one double quote.</p>
*
* <p>If the value is not enclosed in double quotes, or is and does not contain a
* comma, newline or double quote, then the String value is returned unchanged.</p>
*
* see <a href="https://en.wikipedia.org/wiki/Comma-separated_values">Wikipedia</a> and
* <a href="https://datatracker.ietf.org/doc/html/rfc4180">RFC 4180</a>.
*
* @param input the input CSV column String, may be null
* @return the input String, with enclosing double quotes removed and embedded double
* quotes unescaped, {@code null} if null string input
* @since 2.4
*/
public static final String unescapeCsv(final String input) {
return UNESCAPE_CSV.translate(input);
}
/**
* Unescapes any EcmaScript literals found in the {@link String}.
*
* <p>For example, it will turn a sequence of {@code '\'} and {@code 'n'}
* into a newline character, unless the {@code '\'} is preceded by another
* {@code '\'}.</p>
*
* @see #unescapeJava(String)
* @param input the {@link String} to unescape, may be null
* @return A new unescaped {@link String}, {@code null} if null string input
* @since 3.0
*/
public static final String unescapeEcmaScript(final String input) {
return UNESCAPE_ECMASCRIPT.translate(input);
}
/**
* Unescapes a string containing entity escapes to a string
* containing the actual Unicode characters corresponding to the
* escapes. Supports only HTML 3.0 entities.
*
* @param input the {@link String} to unescape, may be null
* @return a new unescaped {@link String}, {@code null} if null string input
* @since 3.0
*/
public static final String unescapeHtml3(final String input) {
return UNESCAPE_HTML3.translate(input);
}
/**
* Unescapes a string containing entity escapes to a string
* containing the actual Unicode characters corresponding to the
* escapes. Supports HTML 4.0 entities.
*
* <p>For example, the string {@code "<Français>"}
* will become {@code "<Français>"}</p>
*
* <p>If an entity is unrecognized, it is left alone, and inserted
* verbatim into the result string. e.g. {@code ">&zzzz;x"} will
* become {@code ">&zzzz;x"}.</p>
*
* @param input the {@link String} to unescape, may be null
* @return a new unescaped {@link String}, {@code null} if null string input
* @since 3.0
*/
public static final String unescapeHtml4(final String input) {
return UNESCAPE_HTML4.translate(input);
}
/**
* Unescapes any Java literals found in the {@link String}.
* For example, it will turn a sequence of {@code '\'} and
* {@code 'n'} into a newline character, unless the {@code '\'}
* is preceded by another {@code '\'}.
*
* @param input the {@link String} to unescape, may be null
* @return a new unescaped {@link String}, {@code null} if null string input
*/
public static final String unescapeJava(final String input) {
return UNESCAPE_JAVA.translate(input);
}
/**
* Unescapes any Json literals found in the {@link String}.
*
* <p>For example, it will turn a sequence of {@code '\'} and {@code 'n'}
* into a newline character, unless the {@code '\'} is preceded by another
* {@code '\'}.</p>
*
* @see #unescapeJava(String)
* @param input the {@link String} to unescape, may be null
* @return A new unescaped {@link String}, {@code null} if null string input
* @since 3.2
*/
public static final String unescapeJson(final String input) {
return UNESCAPE_JSON.translate(input);
}
/**
* Unescapes a string containing XML entity escapes to a string
* containing the actual Unicode characters corresponding to the
* escapes.
*
* <p>Supports only the five basic XML entities (gt, lt, quot, amp, apos).
* Does not support DTDs or external entities.</p>
*
* <p>Note that numerical \\u Unicode codes are unescaped to their respective
* Unicode characters. This may change in future releases.</p>
*
* @param input the {@link String} to unescape, may be null
* @return a new unescaped {@link String}, {@code null} if null string input
* @see #escapeXml(String)
* @see #escapeXml10(String)
* @see #escapeXml11(String)
*/
public static final String unescapeXml(final String input) {
return UNESCAPE_XML.translate(input);
}
/**
* {@link StringEscapeUtils} instances should NOT be constructed in
* standard programming.
*
* <p>Instead, the class should be used as:</p>
* <pre>StringEscapeUtils.escapeJava("foo");</pre>
*
* <p>This constructor is public to permit tools that require a JavaBean
* instance to operate.</p>
*
* @deprecated TODO Make private in 4.0.
*/
@Deprecated
public StringEscapeUtils() {
// empty
}
}