org.fife.ui.rsyntaxtextarea.modes
Class JavaScriptTokenMaker

java.lang.Object
  org.fife.ui.rsyntaxtextarea.TokenMakerBase
      org.fife.ui.rsyntaxtextarea.AbstractJFlexTokenMaker
          org.fife.ui.rsyntaxtextarea.AbstractJFlexCTokenMaker
              org.fife.ui.rsyntaxtextarea.modes.JavaScriptTokenMaker

All Implemented Interfaces:

TokenMaker

public class JavaScriptTokenMaker
extends AbstractJFlexCTokenMaker

Scanner for JavaScript files. Its states could be simplified, but are kept the way they are to keep a degree of similarity (i.e. copy/paste) between it and HTML/JSP/PHPTokenMaker. This should cause no difference in performance.

This implementation was created using JFlex 1.4.1; however, the generated file was modified for performance. Memory allocation needs to be almost completely removed to be competitive with the handwritten lexers (subclasses of AbstractTokenMaker, so this class has been modified so that Strings are never allocated (via yytext()), and the scanner never has to worry about refilling its buffer (needlessly copying chars around). We can achieve this because RText always scans exactly 1 line of tokens at a time, and hands the scanner this line as an array of characters (a Segment really). Since tokens contain pointers to char arrays instead of Strings holding their contents, there is no need for allocating new memory for Strings.

The actual algorithm generated for scanning has, of course, not been modified.

If you wish to regenerate this file yourself, keep in mind the following:

• The generated JavaScriptTokenMaker.java file will contain two definitions of both zzRefill and yyreset. You should hand-delete the second of each definition (the ones generated by the lexer), as these generated methods modify the input buffer, which we'll never have to do.
• You should also change the declaration/definition of zzBuffer to NOT be initialized. This is a needless memory allocation for us since we will be pointing the array somewhere else anyway.
• You should NOT call yylex() on the generated scanner directly; rather, you should use getTokenList as you would with any other TokenMaker instance.

Nested Class Summary

Nested classes/interfaces inherited from class org.fife.ui.rsyntaxtextarea.AbstractJFlexCTokenMaker

AbstractJFlexCTokenMaker.CStyleInsertBreakAction

Field Summary

static int	E4X
static int	E4X_CDATA
static int	E4X_COMMENT
static int	E4X_DTD
static int	E4X_INATTR_DOUBLE
static int	E4X_INATTR_SINGLE
static int	E4X_INTAG
static int	E4X_PI
static int	JS_CHAR
static int	JS_DOCCOMMENT
static int	JS_EOL_COMMENT
static int	JS_MLC
static int	JS_STRING lexical states
static int	YYEOF This character denotes the end of file
static int	YYINITIAL

Fields inherited from class org.fife.ui.rsyntaxtextarea.AbstractJFlexTokenMaker

offsetShift, s, start

Fields inherited from class org.fife.ui.rsyntaxtextarea.TokenMakerBase

currentToken, firstToken, previousToken

Constructor Summary

JavaScriptTokenMaker()
Constructor.

JavaScriptTokenMaker(java.io.InputStream in)
Creates a new scanner.

JavaScriptTokenMaker(java.io.Reader in)
Creates a new scanner There is also a java.io.InputStream version of this constructor.

Method Summary

void	addToken(char[] array, int start, int end, int tokenType, int startOffset) Adds the token specified to the current linked list of tokens.
int	getClosestStandardTokenTypeForInternalType(int type) Returns the closest "standard" token type for a given "internal" token type (e.g.
static java.lang.String	getJavaScriptVersion() Returns the JavaScript version being highlighted.
java.lang.String[]	getLineCommentStartAndEnd(int languageIndex) Returns the text to place at the beginning and end of a line to "comment" it in this programming language.
Token	getTokenList(javax.swing.text.Segment text, int initialTokenType, int startOffset) Returns the first token in the linked list of tokens generated from text.
static boolean	isE4xSupported() Returns whether e4x is being highlighted.
static boolean	isJavaScriptCompatible(java.lang.String version) Returns whether features for a specific JS version should be honored while highlighting.
static void	setE4xSupported(boolean supported) Sets whether e4x should be highlighted.
static void	setJavaScriptVersion(java.lang.String javaScriptVersion) Set the supported JavaScript version because some keywords were introduced on or after this version.
void	yybegin(int newState) Enters a new lexical state
char	yycharat(int pos) Returns the character at position pos from the matched text.
void	yyclose() Closes the input stream.
int	yylength() Returns the length of the matched text region.
Token	yylex() Resumes scanning until the next regular expression is matched, the end of input is encountered or an I/O-Error occurs.
void	yypushback(int number) Pushes the specified amount of characters back into the input stream.
void	yyreset(java.io.Reader reader) Resets the scanner to read from a new input stream.
int	yystate() Returns the current lexical state.
java.lang.String	yytext() Returns the text matched by the current regular expression.

Methods inherited from class org.fife.ui.rsyntaxtextarea.AbstractJFlexCTokenMaker

createInsertBreakAction, getCurlyBracesDenoteCodeBlocks, getInsertBreakAction, getMarkOccurrencesOfTokenType, getShouldIndentNextLineAfter

Methods inherited from class org.fife.ui.rsyntaxtextarea.AbstractJFlexTokenMaker

yybegin

Methods inherited from class org.fife.ui.rsyntaxtextarea.TokenMakerBase

addNullToken, addToken, addToken, createOccurrenceMarker, getLanguageIndex, getLastTokenTypeOnLine, getOccurrenceMarker, isIdentifierChar, isMarkupLanguage, resetTokenList, setLanguageIndex

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

YYEOF

public static final int YYEOF

This character denotes the end of file

See Also:

Constant Field Values

JS_STRING

public static final int JS_STRING

lexical states

See Also:

Constant Field Values

E4X

public static final int E4X

See Also:

Constant Field Values

E4X_INTAG

public static final int E4X_INTAG

See Also:

Constant Field Values

E4X_PI

public static final int E4X_PI

See Also:

Constant Field Values

JS_MLC

public static final int JS_MLC

See Also:

Constant Field Values

JS_CHAR

public static final int JS_CHAR

See Also:

Constant Field Values

JS_EOL_COMMENT

public static final int JS_EOL_COMMENT

See Also:

Constant Field Values

E4X_COMMENT

public static final int E4X_COMMENT

See Also:

Constant Field Values

JS_DOCCOMMENT

public static final int JS_DOCCOMMENT

See Also:

Constant Field Values

E4X_DTD

public static final int E4X_DTD

See Also:

Constant Field Values

E4X_INATTR_SINGLE

public static final int E4X_INATTR_SINGLE

See Also:

Constant Field Values

E4X_INATTR_DOUBLE

public static final int E4X_INATTR_DOUBLE

See Also:

Constant Field Values

YYINITIAL

public static final int YYINITIAL

See Also:

Constant Field Values

E4X_CDATA

public static final int E4X_CDATA

See Also:

Constant Field Values

Constructor Detail

JavaScriptTokenMaker

public JavaScriptTokenMaker()

Constructor. This must be here because JFlex does not generate a no-parameter constructor.

JavaScriptTokenMaker

public JavaScriptTokenMaker(java.io.Reader in)

Creates a new scanner There is also a java.io.InputStream version of this constructor.

Parameters:

in - the java.io.Reader to read input from.

JavaScriptTokenMaker

public JavaScriptTokenMaker(java.io.InputStream in)

Creates a new scanner. There is also java.io.Reader version of this constructor.

Parameters:

in - the java.io.Inputstream to read input from.

Method Detail

addToken

public void addToken(char[] array,
                     int start,
                     int end,
                     int tokenType,
                     int startOffset)

Adds the token specified to the current linked list of tokens.

Specified by:

addToken in interface TokenMaker

Overrides:

addToken in class TokenMakerBase

Parameters:

array - The character array.

start - The starting offset in the array.

end - The ending offset in the array.

tokenType - The token's type.

startOffset - The offset in the document at which this token occurs.

getClosestStandardTokenTypeForInternalType

public int getClosestStandardTokenTypeForInternalType(int type)

Returns the closest "standard" token type for a given "internal" token type (e.g. one whose value is < 0).

Specified by:

getClosestStandardTokenTypeForInternalType in interface TokenMaker

Overrides:

getClosestStandardTokenTypeForInternalType in class TokenMakerBase

Parameters:

type - The token type.

Returns:

The closest "standard" token type.

getJavaScriptVersion

public static java.lang.String getJavaScriptVersion()

Returns the JavaScript version being highlighted.

Returns:

Supported JavaScript version.

See Also:

isJavaScriptCompatible(String)

getLineCommentStartAndEnd

public java.lang.String[] getLineCommentStartAndEnd(int languageIndex)

Returns the text to place at the beginning and end of a line to "comment" it in this programming language.

Specified by:

getLineCommentStartAndEnd in interface TokenMaker

Overrides:

getLineCommentStartAndEnd in class TokenMakerBase

Parameters:

languageIndex - The language index at the offset in question. Since some TokenMakers effectively have nested languages (such as JavaScript in HTML), this parameter tells the TokenMaker what sub-language to look at.

Returns:

The start and end strings to add to a line to "comment" it out. A null value for either means there is no string to add for that part. A value of null for the array means this language does not support commenting/uncommenting lines.

getTokenList

public Token getTokenList(javax.swing.text.Segment text,
                          int initialTokenType,
                          int startOffset)

Returns the first token in the linked list of tokens generated from text. This method must be implemented by subclasses so they can correctly implement syntax highlighting.

Parameters:

text - The text from which to get tokens.

initialTokenType - The token type we should start with.

startOffset - The offset into the document at which text starts.

Returns:

The first Token in a linked list representing the syntax highlighted text.

isE4xSupported

public static boolean isE4xSupported()

Returns whether e4x is being highlighted.

Returns:

Whether e4x is being highlighted.

See Also:

setE4xSupported(boolean)

isJavaScriptCompatible

public static boolean isJavaScriptCompatible(java.lang.String version)

Returns whether features for a specific JS version should be honored while highlighting.

Parameters:

version - JavaScript version required

Returns:

Whether the JavaScript version is the same or greater than version required.

setE4xSupported

public static void setE4xSupported(boolean supported)

Sets whether e4x should be highlighted. A repaint should be forced on all RSyntaxTextAreas editing JavaScript if this property is changed to see the difference.

Parameters:

supported - Whether e4x should be highlighted.

See Also:

isE4xSupported()

setJavaScriptVersion

public static void setJavaScriptVersion(java.lang.String javaScriptVersion)

Set the supported JavaScript version because some keywords were introduced on or after this version.

Parameters:

javaScriptVersion - The version of JavaScript to support, such as "1.5" or "1.6".

See Also:

isJavaScriptCompatible(String), getJavaScriptVersion()

yyreset

public final void yyreset(java.io.Reader reader)

Resets the scanner to read from a new input stream. Does not close the old reader. All internal variables are reset, the old input stream cannot be reused (internal buffer is discarded and lost). Lexical state is set to YY_INITIAL.

Parameters:

reader - the new input stream

yyclose

public final void yyclose()
                   throws java.io.IOException

Closes the input stream.

Throws:

java.io.IOException

yystate

public final int yystate()

Returns the current lexical state.

yybegin

public final void yybegin(int newState)

Enters a new lexical state

Specified by:

yybegin in class AbstractJFlexTokenMaker

Parameters:

newState - the new lexical state

yytext

public final java.lang.String yytext()

Returns the text matched by the current regular expression.

yycharat

public final char yycharat(int pos)

Returns the character at position pos from the matched text. It is equivalent to yytext().charAt(pos), but faster

Parameters:

pos - the position of the character to fetch. A value from 0 to yylength()-1.

Returns:

the character at position pos

yylength

public final int yylength()

Returns the length of the matched text region.

yypushback

public void yypushback(int number)

Pushes the specified amount of characters back into the input stream. They will be read again by then next call of the scanning method

Parameters:

number - the number of characters to be read again. This number must not be greater than yylength()!

yylex

public Token yylex()
            throws java.io.IOException

Resumes scanning until the next regular expression is matched, the end of input is encountered or an I/O-Error occurs.

Returns:

the next token

Throws:

java.io.IOException - if any I/O-Error occurs