* This class, together with its subclasses, contains static methods to perform most required operations * without having to instantiate an object. *
* 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. *
* CharacterReference instances are obtained using one of the following methods:
*
* 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 unicode 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. *
* If this character reference represents a unicode * supplimentary code point, * any bits outside of the least significant 16 bits of the code point are truncated, yielding an incorrect result. *
* To ensure that the character is correctly appended to an Appendable object such as a Writer, use the code:
* characterReference.{@link #appendCharTo(Appendable) appendCharTo}(appendable)
* instead of:
* appendable.append(characterReference.getChar())
*
* @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.
*
* If this character is a unicode supplementary character,
* then both the UTF-16 high/low surrogate char values of the of the character are appended, as described in the
* Unicode character representations section of the
* java.lang.Character class.
*
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to true (the default),
* then calling this method on a non-breaking space character reference ({@link CharacterEntityReference#_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 (;).
*
* Conversely, this library defines an unterminated character reference as one which does * not end with a semicolon. *
* The SGML specification allows unterminated character references in some circumstances, and because the * HTML 4.01 specification states simply that * "authors may use SGML character references", * it follows that they are also valid in HTML documents, although their use is strongly discouraged. *
* Unterminated character references are not allowed in XHTML documents.
*
* @return true if this character reference is terminated by a semicolon, otherwise false.
* @see #decode(CharSequence encodedText, boolean insideAttributeValue)
*/
public boolean isTerminated() {
return source.charAt(end-1)==';';
}
/**
* Encodes the specified text, escaping special characters into character references.
*
* Each character is encoded only if the {@link #requiresEncoding(char)} method would return true for that character,
* using its {@link CharacterEntityReference} if available, or a decimal {@link NumericCharacterReference} if its unicode
* code point is greater than U+007F.
*
* 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 "'".
*
* This method never encodes an apostrophe into its character entity reference {@link CharacterEntityReference#_apos '} * as this entity is not defined for use in HTML. See the comments in the {@link CharacterEntityReference} class for more information. *
* To encode text using only numeric character references, use the
* {@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}.
*
* 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. *
* This performs the same encoding as the {@link #encode(CharSequence)} method, but also performs the following conversions: *
<br />". CR/LF pairs are treated as a single line break.
* "
* while ensuring the last is always a normal space.
* * 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. *
* Note that zero-width spaces (U+200B) are converted to the numeric character reference
* "​" through the normal encoding process, but IE6 does not render them properly
* either encoded or unencoded.
*
* 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. *
* All {@linkplain CharacterEntityReference character entity references} and {@linkplain NumericCharacterReference numeric character references} * are converted to their respective characters. *
* This is equivalent to {@link #decode(CharSequence,boolean) decode(encodedText,false)}. *
* Unterminated character references are dealt with according to the rules for * text outside of attribute values in the {@linkplain Config#CurrentCompatibilityMode current compatibility mode}. *
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to true (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp }) character entity references are converted to normal spaces.
*
* 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. *
* All {@linkplain CharacterEntityReference character entity references} and {@linkplain NumericCharacterReference numeric character references} * are converted to their respective characters. *
* Unterminated character references are dealt with according to the
* value of the insideAttributeValue parameter and the
* {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
*
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to true (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp }) character entity references are converted to normal spaces.
*
* 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
* The result is how the text would normally be rendered by a
* user agent,
* assuming it does not contain any tags.
*
* If the static {@link Config#ConvertNonBreakingSpaces} property is set to
* Unterminated 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
* This process ensures that the specified encoded text does not contain any remaining unencoded characters.
*
* 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.
*
* 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.
*
*
* 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.
*
* The only exception to this is an {@linkplain CharacterEntityReference#_apos apostrophe} (U+0027),
* which is encoded as the numeric character reference "
*
* This is equivalent to {@link #getDecimalCharacterReferenceString(int) getDecimalCharacterReferenceString}
*
*
* This is equivalent to {@link #getHexadecimalCharacterReferenceString(int) getHexadecimalCharacterReferenceString}
*
*
* This is equivalent to {@link #getUnicodeText(int) getUnicodeText(getCodePoint())}.
*
*
*
* 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.
*
* If the text does not represent a valid character reference, this method returns
* Unterminated character references are always accepted, regardless of the settings in the
* {@linkplain Config#CurrentCompatibilityMode current compatibility mode}.
*
* To decode all character references in a given text, use the {@link #decode(CharSequence)} method instead.
*
*
* The character reference must be at the start of the given text, but may contain other characters at the end.
*
* If the text does not represent a valid character reference, this method returns {@link #INVALID_CODE_POINT}.
*
* This is equivalent to {@link #parse(CharSequence) parse(characterReferenceText)}
*
* 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.
*
* The only exception to this is an {@linkplain CharacterEntityReference#_apos apostrophe} (U+0027),
* which only returns true (the default),
* then all non-breaking space ({@link CharacterEntityReference#_nbsp }) character entity references are converted to normal spaces.
* insideAttributeValue 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.
*
*
*
* @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.
* CharacterReference.parse(">").getCharacterReferenceString() returns ">"CharacterReference.parse(">").getCharacterReferenceString() returns "e;"'" instead of its character entity reference
* "'".
*
*
*
* @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 decimal encoded form of this character reference.
* CharacterReference.getCharacterReferenceString(62) returns ">"CharacterReference.getCharacterReferenceString('>') returns ">"CharacterReference.getCharacterReferenceString('☺') returns "☺"({@link #getCodePoint()}).
*
*
*
* @return the decimal encoded form of this character reference.
* @see #getCharacterReferenceString()
* @see #getHexadecimalCharacterReferenceString()
*/
public String getDecimalCharacterReferenceString() {
return getDecimalCharacterReferenceString(codePoint);
}
/**
* Returns the decimal encoded form of the specified unicode code point.
* CharacterReference.parse(">").getDecimalCharacterReferenceString() returns ">"
*
*
* @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 hexadecimal encoded form of this character reference.
* CharacterReference.getDecimalCharacterReferenceString('>') returns ">"({@link #getCodePoint()}).
*
*
*
* @return the hexadecimal encoded form of this character reference.
* @see #getCharacterReferenceString()
* @see #getDecimalCharacterReferenceString()
*/
public String getHexadecimalCharacterReferenceString() {
return getHexadecimalCharacterReferenceString(codePoint);
}
/**
* Returns the hexadecimal encoded form of the specified unicode code point.
* CharacterReference.parse(">").getHexadecimalCharacterReferenceString() returns ">"
*
*
* @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 U+ notation.
* CharacterReference.getHexadecimalCharacterReferenceString('>') returns ">"
*
*
* @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 U+ notation.
* CharacterReference.parse(">").getUnicodeText() returns "U+003E"
*
*
* @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 CharacterReference.getUnicodeText('>') returns "U+003E"CharacterReference object.
* null.
*
*
*
* @param characterReferenceText the text containing a single encoded character reference.
* @return a CharacterReference.parse(">").getChar() returns '>'CharacterReference object representing the specified text, or null 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.
* .{@link #getCodePoint()},
* except that it returns {@link #INVALID_CODE_POINT} if an invalid character reference is specified instead of throwing a
* NullPointerException.
*
*
*
* @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.
* CharacterReference.getCodePointFromCharacterReferenceString(">") returns 38true if the static {@link Config#IsApostropheEncoded} property
* is currently set to true.
*
* @param ch the character to test.
* @return true if the specified character would need to be encoded in HTML text, otherwise false.
*/
public static final boolean requiresEncoding(final char ch) {
return ch>127 || (CharacterEntityReference.getName(ch)!=null && (ch!='\'' || Config.IsApostropheEncoded));
}
/**
* Returns a filter Writer that {@linkplain #encode(CharSequence) encodes} all text before passing it through to the specified Writer.
*
* @param writer the destination for the encoded text
* @return a filter Writer that {@linkplain #encode(CharSequence) encodes} all text before passing it through to the specified Writer.
* @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