Class LatexTokenMaker

  • All Implemented Interfaces:
    TokenMaker

    public class LatexTokenMaker
    extends AbstractJFlexTokenMaker
    Scanner for the LaTeX.

    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 RSTA 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 LatexTokenMaker.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.
    Version:
    0.5
    • Field Detail

      • YYEOF

        public static final int YYEOF
        This character denotes the end of file
        See Also:
        Constant Field Values
      • ZZ_CMAP_PACKED

        private static final java.lang.String ZZ_CMAP_PACKED
        Translates characters to character classes
        See Also:
        Constant Field Values
      • ZZ_CMAP

        private static final char[] ZZ_CMAP
        Translates characters to character classes
      • ZZ_ACTION

        private static final int[] ZZ_ACTION
        Translates DFA states to action switch labels.
      • ZZ_ACTION_PACKED_0

        private static final java.lang.String ZZ_ACTION_PACKED_0
        See Also:
        Constant Field Values
      • ZZ_ROWMAP

        private static final int[] ZZ_ROWMAP
        Translates a state to a row index in the transition table
      • ZZ_ROWMAP_PACKED_0

        private static final java.lang.String ZZ_ROWMAP_PACKED_0
        See Also:
        Constant Field Values
      • ZZ_TRANS

        private static final int[] ZZ_TRANS
        The transition table of the DFA
      • ZZ_TRANS_PACKED_0

        private static final java.lang.String ZZ_TRANS_PACKED_0
        See Also:
        Constant Field Values
      • ZZ_ERROR_MSG

        private static final java.lang.String[] ZZ_ERROR_MSG
      • ZZ_ATTRIBUTE

        private static final int[] ZZ_ATTRIBUTE
        ZZ_ATTRIBUTE[aState] contains the attributes of state aState
      • ZZ_ATTRIBUTE_PACKED_0

        private static final java.lang.String ZZ_ATTRIBUTE_PACKED_0
        See Also:
        Constant Field Values
      • zzReader

        private java.io.Reader zzReader
        the input device
      • zzState

        private int zzState
        the current state of the DFA
      • zzLexicalState

        private int zzLexicalState
        the current lexical state
      • zzBuffer

        private char[] zzBuffer
        this buffer contains the current text to be matched and is the source of the yytext() string
      • zzMarkedPos

        private int zzMarkedPos
        the textposition at the last accepting state
      • zzCurrentPos

        private int zzCurrentPos
        the current text position in the buffer
      • zzStartRead

        private int zzStartRead
        startRead marks the beginning of the yytext() string in the buffer
      • zzEndRead

        private int zzEndRead
        endRead marks the last character in the buffer, that has been read from input
      • zzAtEOF

        private boolean zzAtEOF
        zzAtEOF == true <=> the scanner is at the EOF
    • Constructor Detail

      • LatexTokenMaker

        public LatexTokenMaker()
        Constructor. This must be here because JFlex does not generate a no-parameter constructor.
      • LatexTokenMaker

        public LatexTokenMaker​(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.
      • LatexTokenMaker

        public LatexTokenMaker​(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

      • zzUnpackAction

        private static int[] zzUnpackAction()
      • zzUnpackAction

        private static int zzUnpackAction​(java.lang.String packed,
                                          int offset,
                                          int[] result)
      • zzUnpackRowMap

        private static int[] zzUnpackRowMap()
      • zzUnpackRowMap

        private static int zzUnpackRowMap​(java.lang.String packed,
                                          int offset,
                                          int[] result)
      • zzUnpackTrans

        private static int[] zzUnpackTrans()
      • zzUnpackTrans

        private static int zzUnpackTrans​(java.lang.String packed,
                                         int offset,
                                         int[] result)
      • zzUnpackAttribute

        private static int[] zzUnpackAttribute()
      • zzUnpackAttribute

        private static int zzUnpackAttribute​(java.lang.String packed,
                                             int offset,
                                             int[] result)
      • addHyperlinkToken

        private void addHyperlinkToken​(int start,
                                       int end,
                                       int tokenType)
        Adds the token specified to the current linked list of tokens.
        Parameters:
        tokenType - The token's type.
        See Also:
        addToken(int, int, int)
      • addToken

        private void addToken​(int tokenType)
        Adds the token specified to the current linked list of tokens.
        Parameters:
        tokenType - The token's type.
      • addToken

        private void addToken​(int start,
                              int end,
                              int tokenType)
        Adds the token specified to the current linked list of tokens.
        Parameters:
        tokenType - The token's type.
        See Also:
        addHyperlinkToken(int, int, int)
      • addToken

        public void addToken​(char[] array,
                             int start,
                             int end,
                             int tokenType,
                             int startOffset,
                             boolean hyperlink)
        Adds the token specified to the current linked list of tokens.
        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.
        hyperlink - Whether this token is a hyperlink.
      • getLineCommentStartAndEnd

        public java.lang.String[] getLineCommentStartAndEnd​(int languageIndex)
        ${inheritDoc}
        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.
      • zzRefill

        private boolean zzRefill()
        Refills the input buffer.
        Returns:
        true if EOF was reached, otherwise false.
      • 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
      • zzUnpackCMap

        private static char[] zzUnpackCMap​(java.lang.String packed)
        Unpacks the compressed character translation table.
        Parameters:
        packed - the packed character translation table
        Returns:
        the unpacked character translation table
      • yyclose

        public final void yyclose()
                           throws java.io.IOException
        Closes the input stream.
        Specified by:
        yyclose in class AbstractJFlexTokenMaker
        Throws:
        java.io.IOException - If an IO error occurs.
      • 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.
        Specified by:
        yytext in class AbstractJFlexTokenMaker
      • 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.
      • zzScanError

        private void zzScanError​(int errorCode)
        Reports an error that occured while scanning. In a wellformed scanner (no or only correct usage of yypushback(int) and a match-all fallback rule) this method will only be called with things that "Can't Possibly Happen". If this method is called, something is seriously wrong (e.g. a JFlex bug producing a faulty scanner etc.). Usual syntax/scanner level error handling should be done in error fallback rules.
        Parameters:
        errorCode - the code of the errormessage to display
      • 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