// Jericho HTML Parser - Java based library for analysing and manipulating HTML
// Version 3.1
// Copyright (C) 2004-2009 Martin Jericho
// http://jericho.htmlparser.net/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of either one of the following licences:
//
// 1. The Eclipse Public License (EPL) version 1.0,
// included in this distribution in the file licence-epl-1.0.html
// or available at http://www.eclipse.org/legal/epl-v10.html
//
// 2. The GNU Lesser General Public License (LGPL) version 2.1 or later,
// included in this distribution in the file licence-lgpl-2.1.txt
// or available at http://www.gnu.org/licenses/lgpl.txt
//
// This library is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the individual licence texts for more details.
package net.htmlparser.jericho;
import java.util.*;
import java.io.*;
/**
* Represents an HTML <a target="_blank" href="http://www.w3.org/TR/REC-html40/charset.html#entities">Character Reference</a>,
* implemented by the subclasses {@link CharacterEntityReference} and {@link NumericCharacterReference}.
* <p>
* This class, together with its subclasses, contains static methods to perform most required operations
* without having to instantiate an object.
* <p>
* Instances of this class are useful when the positions of character references in a source document are required,
* or to replace the found character references with customised text.
* <p>
* <code>CharacterReference</code> instances are obtained using one of the following methods:
* <ul>
* <li>{@link CharacterReference#parse(CharSequence characterReferenceText)}
* <li>{@link Source#getNextCharacterReference(int pos)}
* <li>{@link Source#getPreviousCharacterReference(int pos)}
* <li>{@link Segment#getAllCharacterReferences()}
* </ul>
*/
public abstract class CharacterReference extends Segment {
int codePoint;
/**
* Represents an invalid unicode code point.
* <p>
* This can be the result of parsing a numeric character reference outside of the valid unicode range of 0x000000-0x10FFFF, or any other invalid character reference.
*/
public static final int INVALID_CODE_POINT=-1;
static int MAX_ENTITY_REFERENCE_LENGTH; // set in CharacterEntityReference static class initialisation
/** The number of spaces used to simulate a tab when {@linkplain #encodeWithWhiteSpaceFormatting encoding with white space formatting}. */
private static final int TAB_LENGTH=4;
CharacterReference(final Source source, final int begin, final int end, final int codePoint) {
super(source,begin,end);
this.codePoint=codePoint;
}
/**
* Returns the <a target="_blank" href="http://www.unicode.org">unicode</a> code point represented by this character reference.
* @return the unicode code point represented by this character reference.
* @see #appendCharTo(Appendable)
*/
public int getCodePoint() {
return codePoint;
}
/**
* Returns the character represented by this character reference.
* <p>
* If this character reference represents a unicode
* <a target="_blank" href="http://www.unicode.org/glossary/#supplementary_code_point">supplimentary code point</a>,
* any bits outside of the least significant 16 bits of the code point are truncated, yielding an incorrect result.
* <p>
* To ensure that the character is correctly appended to an <code>Appendable</code> object such as a <code>Writer</code>, use the code:
* <br /><code>characterReference.</code>{@link #appendCharTo(Appendable) appendCharTo}<code>(appendable)</code><br />
* instead of:
* <br /><code>appendable.append(characterReference.getChar())</code>
*
* @return the character represented by this character reference.
* @see #appendCharTo(Appendable)
* @see #getCodePoint()
*/
public char getChar() {
return (char)codePoint;
}
/**
* Appends the character represented by this character reference to the specified appendable object.
* <p>
* If this character is a unicode <a target="_blank" href="http://unicode.org/glossary/#supplementary_character">supplementary character</a>,
* then both the UTF-16 high/low surrogate <code>char</code> values of the of the character are appended, as described in the
* <a target="_blank" href="http://java.sun.com/javase/6/docs/api/java/lang/Character.html#unicode">Unicode character representations</a> section of the
* <code>java.lang.Character</code> class.
* <p>
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to <code>true</code> (the default),
* then calling this method on a non-breaking space character reference ({@link CharacterEntityReference#_nbsp &nbsp;})
* results in a normal space being appended.
*
* @param appendable the object to append this character reference to.
*/
public final void appendCharTo(Appendable appendable) throws IOException {
appendCharTo(appendable,Config.ConvertNonBreakingSpaces);
}
private void appendCharTo(Appendable appendable, final boolean convertNonBreakingSpaces) throws IOException {
if (Character.isSupplementaryCodePoint(codePoint)) {
appendable.append(getHighSurrogate(codePoint));
appendable.append(getLowSurrogate(codePoint));
} else {
final char ch=getChar();
if (ch==CharacterEntityReference._nbsp && convertNonBreakingSpaces) {
appendable.append(' ');
} else {
appendable.append(ch);
}
}
}
/**
* Indicates whether this character reference is terminated by a semicolon (<code>;</code>).
* <p>
* Conversely, this library defines an <i><a name="Unterminated">unterminated</a></i> character reference as one which does
* not end with a semicolon.
* <p>
* The SGML specification allows unterminated character references in some circumstances, and because the
* HTML 4.01 specification states simply that
* "<a target="_blank" href="http://www.w3.org/TR/REC-html40/charset.html#entities">authors may use SGML character references</a>",
* it follows that they are also valid in HTML documents, although their use is strongly discouraged.
* <p>
* Unterminated character references are not allowed in <a target="_blank" href="http://www.w3.org/TR/xhtml1/">XHTML</a> documents.
*
* @return <code>true</code> if this character reference is terminated by a semicolon, otherwise <code>false</code>.
* @see #decode(CharSequence encodedText, boolean insideAttributeValue)
*/
public boolean isTerminated() {
return source.charAt(end-1)==';';
}
/**
* Encodes the specified text, escaping special characters into character references.
* <p>
* Each character is encoded only if the {@link #requiresEncoding(char)} method would return <code>true</code> for that character,
* using its {@link CharacterEntityReference} if available, or a decimal {@link NumericCharacterReference} if its unicode
* code point is greater than U+007F.
* <p>
* The only exception to this is an {@linkplain CharacterEntityReference#_apos apostrophe} (U+0027),
* which depending on the current setting of the static {@link Config#IsApostropheEncoded} property,
* is either left unencoded (default setting), or encoded as the numeric character reference "<code>&#39;</code>".
* <p>
* This method never encodes an apostrophe into its character entity reference {@link CharacterEntityReference#_apos &apos;}
* as this entity is not defined for use in HTML. See the comments in the {@link CharacterEntityReference} class for more information.
* <p>
* To encode text using only numeric character references, use the<br />
* {@link NumericCharacterReference#encode(CharSequence)} method instead.
*
* @param unencodedText the text to encode.
* @return the encoded string.
* @see #decode(CharSequence)
*/
public static String encode(final CharSequence unencodedText) {
if (unencodedText==null) return null;
try {
return appendEncode(new StringBuilder(unencodedText.length()*2),unencodedText,false).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
/**
* Encodes the specified character into a character reference if {@linkplain #requiresEncoding(char) required}.
* <p>
* The encoding of the character follows the same rules as for each character in the {@link #encode(CharSequence unencodedText)} method.
*
* @param ch the character to encode.
* @return a character reference if appropriate, otherwise a string containing the original character.
*/
public static String encode(final char ch) {
try {
return appendEncode(new StringBuilder(MAX_ENTITY_REFERENCE_LENGTH),ch).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
/**
* {@linkplain #encode(CharSequence) Encodes} the specified text, preserving line breaks, tabs and spaces for rendering by converting them to markup.
* <p>
* This performs the same encoding as the {@link #encode(CharSequence)} method, but also performs the following conversions:
* <ul>
* <li>Line breaks, being Carriage Return (U+000D) or Line Feed (U+000A) characters, and Form Feed characters (U+000C)
* are converted to "<code><br /></code>". CR/LF pairs are treated as a single line break.
* <li>Multiple consecutive spaces are converted so that every second space is converted to "<code>&nbsp;</code>"
* while ensuring the last is always a normal space.
* <li>Tab characters (U+0009) are converted as if they were four consecutive spaces.
* </ul>
* <p>
* The conversion of multiple consecutive spaces to alternating space/non-breaking-space allows the correct number of
* spaces to be rendered, but also allows the line to wrap in the middle of it.
* <p>
* Note that zero-width spaces (U+200B) are converted to the numeric character reference
* "<code>&#x200B;</code>" through the normal encoding process, but IE6 does not render them properly
* either encoded or unencoded.
* <p>
* There is no method provided to reverse this encoding.
*
* @param unencodedText the text to encode.
* @return the encoded string with white space formatting converted to markup.
* @see #encode(CharSequence)
*/
public static String encodeWithWhiteSpaceFormatting(final CharSequence unencodedText) {
if (unencodedText==null) return null;
try {
return appendEncode(new StringBuilder(unencodedText.length()*2),unencodedText,true).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
/**
* Decodes the specified HTML encoded text into normal text.
* <p>
* All {@linkplain CharacterEntityReference character entity references} and {@linkplain NumericCharacterReference numeric character references}
* are converted to their respective characters.
* <p>
* This is equivalent to {@link #decode(CharSequence,boolean) decode(encodedText,false)}.
* <p>
* <a href="#Unterminated">Unterminated</a> character references are dealt with according to the rules for
* text outside of attribute values in the {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
* <p>
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to <code>true</code> (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp &nbsp;}) character entity references are converted to normal spaces.
* <p>
* Although character entity reference names are case sensitive, and in some cases differ from other entity references only by their case,
* some browsers also recognise them in a case-insensitive way.
* For this reason, all decoding methods in this library recognise character entity reference names even if they are in the wrong case.
*
* @param encodedText the text to decode.
* @return the decoded string.
* @see #encode(CharSequence)
*/
public static String decode(final CharSequence encodedText) {
return decode(encodedText,false,Config.ConvertNonBreakingSpaces);
}
/**
* Decodes the specified HTML encoded text into normal text.
* <p>
* All {@linkplain CharacterEntityReference character entity references} and {@linkplain NumericCharacterReference numeric character references}
* are converted to their respective characters.
* <p>
* <a href="#Unterminated">Unterminated</a> character references are dealt with according to the
* value of the <code>insideAttributeValue</code> parameter and the
* {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
* <p>
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to <code>true</code> (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp &nbsp;}) character entity references are converted to normal spaces.
* <p>
* Although character entity reference names are case sensitive, and in some cases differ from other entity references only by their case,
* some browsers also recognise them in a case-insensitive way.
* For this reason, all decoding methods in this library recognise character entity reference names even if they are in the wrong case.
*
* @param encodedText the text to decode.
* @param insideAttributeValue specifies whether the encoded text is inside an attribute value.
* @return the decoded string.
* @see #decode(CharSequence)
* @see #encode(CharSequence)
*/
public static String decode(final CharSequence encodedText, final boolean insideAttributeValue) {
return decode(encodedText,insideAttributeValue,Config.ConvertNonBreakingSpaces);
}
static String decode(final CharSequence encodedText, final boolean insideAttributeValue, final boolean convertNonBreakingSpaces) {
if (encodedText==null) return null;
for (int i=0; i<encodedText.length(); i++) {
if (encodedText.charAt(i)=='&') {
try {
return appendDecode(new StringBuilder(encodedText.length()),encodedText,i,insideAttributeValue,convertNonBreakingSpaces).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
}
return encodedText.toString();
}
/**
* {@linkplain #decode(CharSequence) Decodes} the specified text after collapsing its {@linkplain #isWhiteSpace(char) white space}.
* <p>
* All leading and trailing white space is omitted, and any sections of internal white space are replaced by a single space.
* <p>
* The result is how the text would normally be rendered by a
* <a target="_blank" href="http://www.w3.org/TR/html401/conform.html#didx-user_agent">user agent</a>,
* assuming it does not contain any tags.
* <p>
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to <code>true</code> (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp &nbsp;}) character entity references are converted to normal spaces.
* <p>
* <a href="#Unterminated">Unterminated</a> character references are dealt with according to the rules for
* text outside of attribute values in the {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
* See the discussion of the <code>insideAttributeValue</code> parameter of the {@link #decode(CharSequence, boolean insideAttributeValue)}
* method for a more detailed explanation of this topic.
*
* @param text the source text
* @return the decoded text with collapsed white space.
* @see FormControl#getPredefinedValues()
*/
public static String decodeCollapseWhiteSpace(final CharSequence text) {
return decodeCollapseWhiteSpace(text,Config.ConvertNonBreakingSpaces);
}
static String decodeCollapseWhiteSpace(final CharSequence text, final boolean convertNonBreakingSpaces) {
return decode(appendCollapseWhiteSpace(new StringBuilder(text.length()),text),false,convertNonBreakingSpaces);
}
/**
* Re-encodes the specified text, equivalent to {@linkplain #decode(CharSequence) decoding} and then {@linkplain #encode(CharSequence) encoding} again.
* <p>
* This process ensures that the specified encoded text does not contain any remaining unencoded characters.
* <p>
* IMPLEMENTATION NOTE: At present this method simply calls the {@link #decode(CharSequence) decode} method
* followed by the {@link #encode(CharSequence) encode} method, but a more efficient implementation
* may be used in future.
*
* @param encodedText the text to re-encode.
* @return the re-encoded string.
*/
public static String reencode(final CharSequence encodedText) {
return encode(decode(encodedText,true));
}
/**
* Returns the encoded form of this character reference.
* <p>
* The exact behaviour of this method depends on the class of this object.
* See the {@link CharacterEntityReference#getCharacterReferenceString()} and
* {@link NumericCharacterReference#getCharacterReferenceString()} methods for more details.
* <p>
* <dl>
* <dt>Examples:</dt>
* <dd><code>CharacterReference.parse("&GT;").getCharacterReferenceString()</code> returns "<code>&gt;</code>"</dd>
* <dd><code>CharacterReference.parse("&#x3E;").getCharacterReferenceString()</code> returns "<code>&#3e;</code>"</dd>
* </dl>
*
* @return the encoded form of this character reference.
* @see #getCharacterReferenceString(int codePoint)
* @see #getDecimalCharacterReferenceString()
*/
public abstract String getCharacterReferenceString();
/**
* Returns the encoded form of the specified unicode code point.
* <p>
* This method returns the {@linkplain CharacterEntityReference#getCharacterReferenceString(int) character entity reference} encoded form of the unicode code point
* if one exists, otherwise it returns the {@linkplain #getDecimalCharacterReferenceString(int) decimal character reference} encoded form.
* <p>
* The only exception to this is an {@linkplain CharacterEntityReference#_apos apostrophe} (U+0027),
* which is encoded as the numeric character reference "<code>&#39;</code>" instead of its character entity reference
* "<code>&apos;</code>".
* <p>
* <dl>
* <dt>Examples:</dt>
* <dd><code>CharacterReference.getCharacterReferenceString(62)</code> returns "<code>&gt;</code>"</dd>
* <dd><code>CharacterReference.getCharacterReferenceString('>')</code> returns "<code>&gt;</code>"</dd>
* <dd><code>CharacterReference.getCharacterReferenceString('☺')</code> returns "<code>&#9786;</code>"</dd>
* </dl>
*
* @param codePoint the unicode code point to encode.
* @return the encoded form of the specified unicode code point.
* @see #getHexadecimalCharacterReferenceString(int codePoint)
*/
public static String getCharacterReferenceString(final int codePoint) {
String characterReferenceString=null;
if (codePoint!=CharacterEntityReference._apos) characterReferenceString=CharacterEntityReference.getCharacterReferenceString(codePoint);
if (characterReferenceString==null) characterReferenceString=NumericCharacterReference.getCharacterReferenceString(codePoint);
return characterReferenceString;
}
/**
* Returns the <a href="NumericCharacterReference.html#DecimalCharacterReference">decimal encoded form</a> of this character reference.
* <p>
* This is equivalent to {@link #getDecimalCharacterReferenceString(int) getDecimalCharacterReferenceString}<code>(</code>{@link #getCodePoint()}<code>)</code>.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.parse("&gt;").getDecimalCharacterReferenceString()</code> returns "<code>&#62;</code>"</dd>
* </dl>
*
* @return the decimal encoded form of this character reference.
* @see #getCharacterReferenceString()
* @see #getHexadecimalCharacterReferenceString()
*/
public String getDecimalCharacterReferenceString() {
return getDecimalCharacterReferenceString(codePoint);
}
/**
* Returns the <a href="NumericCharacterReference.html#DecimalCharacterReference">decimal encoded form</a> of the specified unicode code point.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.getDecimalCharacterReferenceString('>')</code> returns "<code>&#62;</code>"</dd>
* </dl>
*
* @param codePoint the unicode code point to encode.
* @return the decimal encoded form of the specified unicode code point.
* @see #getCharacterReferenceString(int codePoint)
* @see #getHexadecimalCharacterReferenceString(int codePoint)
*/
public static String getDecimalCharacterReferenceString(final int codePoint) {
try {
return appendDecimalCharacterReferenceString(new StringBuilder(),codePoint).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
/**
* Returns the <a href="NumericCharacterReference.html#HexadecimalCharacterReference">hexadecimal encoded form</a> of this character reference.
* <p>
* This is equivalent to {@link #getHexadecimalCharacterReferenceString(int) getHexadecimalCharacterReferenceString}<code>(</code>{@link #getCodePoint()}<code>)</code>.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.parse("&gt;").getHexadecimalCharacterReferenceString()</code> returns "<code>&#x3e;</code>"</dd>
* </dl>
*
* @return the hexadecimal encoded form of this character reference.
* @see #getCharacterReferenceString()
* @see #getDecimalCharacterReferenceString()
*/
public String getHexadecimalCharacterReferenceString() {
return getHexadecimalCharacterReferenceString(codePoint);
}
/**
* Returns the <a href="NumericCharacterReference.html#HexadecimalCharacterReference">hexadecimal encoded form</a> of the specified unicode code point.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.getHexadecimalCharacterReferenceString('>')</code> returns "<code>&#x3e;</code>"</dd>
* </dl>
*
* @param codePoint the unicode code point to encode.
* @return the hexadecimal encoded form of the specified unicode code point.
* @see #getCharacterReferenceString(int codePoint)
* @see #getDecimalCharacterReferenceString(int codePoint)
*/
public static String getHexadecimalCharacterReferenceString(final int codePoint) {
try {
return appendHexadecimalCharacterReferenceString(new StringBuilder(),codePoint).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
/**
* Returns the unicode code point of this character reference in <a target="_blank" href="http://www.unicode.org/reports/tr27/#notation">U+ notation</a>.
* <p>
* This is equivalent to {@link #getUnicodeText(int) getUnicodeText(getCodePoint())}.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.parse("&gt;").getUnicodeText()</code> returns "<code>U+003E</code>"</dd>
* </dl>
*
* @return the unicode code point of this character reference in U+ notation.
* @see #getUnicodeText(int codePoint)
*/
public String getUnicodeText() {
return getUnicodeText(codePoint);
}
/**
* Returns the specified unicode code point in <a target="_blank" href="http://www.unicode.org/reports/tr27/#notation">U+ notation</a>.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.getUnicodeText('>')</code> returns "<code>U+003E</code>"</dd>
* </dl>
*
* @param codePoint the unicode code point.
* @return the specified unicode code point in U+ notation.
*/
public static String getUnicodeText(final int codePoint) {
try {
return appendUnicodeText(new StringBuilder(),codePoint).toString();
} catch (IOException ex) {throw new RuntimeException(ex);} // never happens
}
static final Appendable appendUnicodeText(final Appendable appendable, final int codePoint) throws IOException {
appendable.append("U+");
final String hex=Integer.toString(codePoint,16).toUpperCase();
for (int i=4-hex.length(); i>0; i--) appendable.append('0');
appendable.append(hex);
return appendable;
}
/**
* Parses a single encoded character reference text into a <code>CharacterReference</code> object.
* <p>
* The character reference must be at the start of the given text, but may contain other characters at the end.
* The {@link #getEnd() getEnd()} method can be used on the resulting object to determine at which character position the character reference ended.
* <p>
* If the text does not represent a valid character reference, this method returns <code>null</code>.
* <p>
* <a href="#Unterminated">Unterminated</a> character references are always accepted, regardless of the settings in the
* {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
* <p>
* To decode <i>all</i> character references in a given text, use the {@link #decode(CharSequence)} method instead.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.parse("&gt;").getChar()</code> returns '<code>></code>'</dd>
* </dl>
*
* @param characterReferenceText the text containing a single encoded character reference.
* @return a <code>CharacterReference</code> object representing the specified text, or <code>null</code> if the text does not represent a valid character reference.
* @see #decode(CharSequence)
*/
public static CharacterReference parse(final CharSequence characterReferenceText) {
return construct(new Source(characterReferenceText,true),0,Config.UnterminatedCharacterReferenceSettings.ACCEPT_ALL);
}
/**
* Parses a single encoded character reference text into a unicode code point.
* <p>
* The character reference must be at the start of the given text, but may contain other characters at the end.
* <p>
* If the text does not represent a valid character reference, this method returns {@link #INVALID_CODE_POINT}.
* <p>
* This is equivalent to {@link #parse(CharSequence) parse(characterReferenceText)}<code>.</code>{@link #getCodePoint()},
* except that it returns {@link #INVALID_CODE_POINT} if an invalid character reference is specified instead of throwing a
* <code>NullPointerException</code>.
* <p>
* <dl>
* <dt>Example:</dt>
* <dd><code>CharacterReference.getCodePointFromCharacterReferenceString("&gt;")</code> returns <code>38</code></dd>
* </dl>
*
* @param characterReferenceText the text containing a single encoded character reference.
* @return the unicode code point representing representing the specified text, or {@link #INVALID_CODE_POINT} if the text does not represent a valid character reference.
*/
public static int getCodePointFromCharacterReferenceString(final CharSequence characterReferenceText) {
final CharacterReference characterReference=parse(characterReferenceText);
return (characterReference!=null) ? characterReference.getCodePoint() : INVALID_CODE_POINT;
}
/**
* Indicates whether the specified character would need to be encoded in HTML text.
* <p>
* This is the case if a {@linkplain CharacterEntityReference character entity reference} exists for the character, or the unicode code point is greater than U+007F.
* <p>
* The only exception to this is an {@linkplain CharacterEntityReference#_apos apostrophe} (U+0027),
* which only returns <code>true</code> if the static {@link Config#IsApostropheEncoded} property
* is currently set to <code>true</code>.
*
* @param ch the character to test.
* @return <code>true</code> if the specified character would need to be encoded in HTML text, otherwise <code>false</code>.
*/
public static final boolean requiresEncoding(final char ch) {
return ch>127 || (CharacterEntityReference.getName(ch)!=null && (ch!='\'' || Config.IsApostropheEncoded));
}
/**
* Returns a filter <code>Writer</code> that {@linkplain #encode(CharSequence) encodes} all text before passing it through to the specified <code>Writer</code>.
*
* @param writer the destination for the encoded text
* @return a filter <code>Writer</code> that {@linkplain #encode(CharSequence) encodes} all text before passing it through to the specified <code>Writer</code>.
* @see #encode(CharSequence unencodedText)
*/
public static Writer getEncodingFilterWriter(final Writer writer) {
return new EncodingFilterWriter(writer);
}
private static final class EncodingFilterWriter extends FilterWriter {
StringBuilder sb=new StringBuilder(MAX_ENTITY_REFERENCE_LENGTH);
public EncodingFilterWriter(final Writer writer) {
super(writer);
}
public void write(final char ch) throws IOException {
sb.setLength(0);
appendEncode(sb,ch);
if (sb.length()==1)
out.write(sb.charAt(0));
else
out.append(sb);
}
public void write(final int chInt) throws IOException {
write((char)chInt);
}
public void write(final char[] cbuf, final int off, final int len) throws IOException {
final int end=off+len;
for (int i=off; i<end; i++) write(cbuf[i]);
}
public void write(final String str, final int off, final int len) throws IOException {
final int end=off+len;
for (int i=off; i<end; i++) write(str.charAt(i));
}
}
private static Appendable appendEncode(final Appendable appendable, char ch) throws IOException {
if (appendEncodeCheckForWhiteSpaceFormatting(appendable,ch,false)) return appendable;
return appendable.append(ch);
}
static Appendable appendEncode(final Appendable appendable, CharSequence unencodedText, final boolean whiteSpaceFormatting) throws IOException {
if (unencodedText==null) return appendable;
int beginPos=0;
int endPos=unencodedText.length();
if (unencodedText instanceof Segment) {
// this might improve performance slightly
final Segment segment=(Segment)unencodedText;
final int segmentOffset=segment.getBegin();
beginPos=segmentOffset;
endPos+=segmentOffset;
unencodedText=segment.source;
}
final boolean isApostropheEncoded=Config.IsApostropheEncoded;
for (int i=beginPos; i<endPos; i++) {
char ch=unencodedText.charAt(i);
if (appendEncodeCheckForWhiteSpaceFormatting(appendable,ch,whiteSpaceFormatting)) continue;
// need to process white space
// whiteSpaceFormatting tries to simulate the formatting characters by converting them to markup
int spaceCount;
int nexti=i+1;
if (ch!=' ') {
if (ch!='\t') {
// must be line feed, carriage return or form feed, since zero-width space should have been processed as a character reference string
if (ch=='\r' && nexti<endPos && unencodedText.charAt(nexti)=='\n') i++; // process cr/lf pair as one line break
appendable.append("<br />"); // add line break
continue;
} else {
spaceCount=TAB_LENGTH;
}
} else {
spaceCount=1;
}
while (nexti<endPos) {
ch=unencodedText.charAt(nexti);
if (ch==' ')
spaceCount+=1;
else if (ch=='\t')
spaceCount+=TAB_LENGTH;
else
break;
nexti++;
}
if (spaceCount==1) {
// handle the very common case of a single character to improve efficiency slightly
appendable.append(' ');
continue;
}
if (spaceCount%2==1) appendable.append(' '); // fist character is a space if we have an odd number of spaces
while (spaceCount>=2) {
appendable.append(" "); // use alternating and spaces to keep original number of spaces
spaceCount-=2;
}
// note that the last character is never a nbsp, so that word wrapping won't result in a nbsp before the first character in a line
i=nexti-1; // minus 1 because top level for loop will add it again
}
return appendable;
}
private static final boolean appendEncodeCheckForWhiteSpaceFormatting(final Appendable appendable, char ch, final boolean whiteSpaceFormatting) throws IOException {
final String characterEntityReferenceName=CharacterEntityReference.getName(ch);
if (characterEntityReferenceName!=null) {
if (ch=='\'') {
if (Config.IsApostropheEncoded)
appendable.append("'");
else
appendable.append(ch);
} else {
CharacterEntityReference.appendCharacterReferenceString(appendable,characterEntityReferenceName);
}
} else if (ch>127) {
appendDecimalCharacterReferenceString(appendable,ch);
} else if (!(whiteSpaceFormatting && isWhiteSpace(ch))) {
appendable.append(ch);
} else {
return false;
}
return true;
}
static CharacterReference getPrevious(final Source source, final int pos) {
return getPrevious(source,pos,Config.UnterminatedCharacterReferenceSettings.ACCEPT_ALL);
}
static CharacterReference getNext(final Source source, final int pos) {
return getNext(source,pos,Config.UnterminatedCharacterReferenceSettings.ACCEPT_ALL);
}
private static CharacterReference getPrevious(final Source source, int pos, final Config.UnterminatedCharacterReferenceSettings unterminatedCharacterReferenceSettings) {
final ParseText parseText=source.getParseText();
pos=parseText.lastIndexOf('&',pos);
while (pos!=-1) {
final CharacterReference characterReference=construct(source,pos,unterminatedCharacterReferenceSettings);
if (characterReference!=null) return characterReference;
pos=parseText.lastIndexOf('&',pos-1);
}
return null;
}
private static CharacterReference getNext(final Source source, int pos, final Config.UnterminatedCharacterReferenceSettings unterminatedCharacterReferenceSettings) {
final ParseText parseText=source.getParseText();
pos=parseText.indexOf('&',pos);
while (pos!=-1) {
final CharacterReference characterReference=construct(source,pos,unterminatedCharacterReferenceSettings);
if (characterReference!=null) return characterReference;
pos=parseText.indexOf('&',pos+1);
}
return null;
}
static final Appendable appendHexadecimalCharacterReferenceString(final Appendable appendable, final int codePoint) throws IOException {
return appendable.append("&#x").append(Integer.toString(codePoint,16)).append(';');
}
static final Appendable appendDecimalCharacterReferenceString(final Appendable appendable, final int codePoint) throws IOException {
return appendable.append("&#").append(Integer.toString(codePoint)).append(';');
}
static CharacterReference construct(final Source source, final int begin, final Config.UnterminatedCharacterReferenceSettings unterminatedCharacterReferenceSettings) {
try {
if (source.getParseText().charAt(begin)!='&') return null;
return (source.getParseText().charAt(begin+1)=='#')
? NumericCharacterReference.construct(source,begin,unterminatedCharacterReferenceSettings)
: CharacterEntityReference.construct(source,begin,unterminatedCharacterReferenceSettings.characterEntityReferenceMaxCodePoint);
} catch (IndexOutOfBoundsException ex) {
return null;
}
}
private static Appendable appendDecode(final Appendable appendable, final CharSequence encodedText, int pos, final boolean insideAttributeValue, final boolean convertNonBreakingSpaces) throws IOException {
final Config.UnterminatedCharacterReferenceSettings unterminatedCharacterReferenceSettings=Config.CurrentCompatibilityMode.getUnterminatedCharacterReferenceSettings(insideAttributeValue);
int lastEnd=0;
final StreamedSource streamedSource=new StreamedSource(encodedText).setHandleTags(false).setSearchBegin(pos);
for (Segment segment : streamedSource) {
if (segment instanceof CharacterReference) {
((CharacterReference)segment).appendCharTo(appendable,convertNonBreakingSpaces);
} else {
appendable.append(segment.toString()); // benchmark tests reveal (surprisingly) that converting to a string before appending is faster than appending the specified section of the encodedText or segment directly.
// appendable.append(encodedText,segment.begin,segment.end);
// appendable.append(segment);
}
}
return appendable;
}
// pinched from http://svn.apache.org/repos/asf/abdera/java/trunk/dependencies/i18n/src/main/java/org/apache/abdera/i18n/text/CharUtils.java
private static char getHighSurrogate(int codePoint) {
return (char)((0xD800 - (0x10000 >> 10)) + (codePoint >> 10));
}
private static char getLowSurrogate(int codePoint) {
return (char)(0xDC00 + (codePoint & 0x3FF));
}
}
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