JFlex

Class LexScan

Implemented Interfaces:
sym, java_cup.runtime.Scanner

public final class LexScan
extends java.lang.Object
implements sym, java_cup.runtime.Scanner

The lexer of JFlex. Generated by JFlex.

Field Summary

static int
CHARCLASS
static int
COMMENT
static int
COPY
static int
EATWSPNL
static int
JAVA_CODE
static int
MACROS
static int
REGEXP
lexical states
static int
REGEXPSTART
static int
REPEATEXP
static int
STATELIST
static int
STATES
static int
STRING_CONTENT
static int
YYEOF
This character denotes the end of file
static int
YYINITIAL

Fields inherited from interface JFlex.sym

ACTION, BANG, BAR, CCLASS, CCLASSNOT, CHAR, CHAR_I, CLOSEBRACKET, CLOSECLASS, COMMA, CONCAT, DASH, DELIMITER, DIGITCLASS, DOLLAR, EOF, EOFRULE, EQUALS, FULL, HAT, IDENT, JLETTERCLASS, JLETTERDIGITCLASS, LBRACE, LESSTHAN, LETTERCLASS, LOOKAHEAD, LOWERCLASS, MACROUSE, MORETHAN, NOACTION, OPENBRACKET, OPENCLASS, PLUS, POINT, QUESTION, RBRACE, REGEXPEND, REPEAT, STAR, STRING, STRING_I, TILDE, UNICODE, UPPERCLASS, USERCODE, error

Constructor Summary

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

Method Summary

static String
conc(Object a, Object b)
static String
concExc(Object a, Object b)
int
currentLine()
Symbol
debug_next_token()
Same as next_token but also prints the token to standard out for debugging.
static void
main(argv[] )
Runs the scanner on input files.
Symbol
next_token()
Resumes scanning until the next regular expression is matched, the end of input is encountered or an I/O-Error occurs.
void
setFile(File file)
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.
boolean
yymoreStreams()
Returns true iff there are still streams left to read from on the stream stack.
void
yypopStream()
Closes the current input stream and continues to read from the one on top of the stream stack.
void
yypushStream(java.io.Reader reader)
Stores the current input stream on a stack, and reads from a new stream.
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.
String
yytext()
Returns the text matched by the current regular expression.

Field Details

CHARCLASS

public static final int CHARCLASS
Field Value:
18

COMMENT

public static final int COMMENT
Field Value:
2

COPY

public static final int COPY
Field Value:
20

EATWSPNL

public static final int EATWSPNL
Field Value:
24

JAVA_CODE

public static final int JAVA_CODE
Field Value:
12

MACROS

public static final int MACROS
Field Value:
6

REGEXP

public static final int REGEXP
lexical states
Field Value:
10

REGEXPSTART

public static final int REGEXPSTART
Field Value:
8

REPEATEXP

public static final int REPEATEXP
Field Value:
22

STATELIST

public static final int STATELIST
Field Value:
4

STATES

public static final int STATES
Field Value:
14

STRING_CONTENT

public static final int STRING_CONTENT
Field Value:
16

YYEOF

public static final int YYEOF
This character denotes the end of file
Field Value:
-1

YYINITIAL

public static final int YYINITIAL
Field Value:
0

Constructor Details

LexScan

public LexScan(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.

LexScan

public LexScan(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.

Method Details

conc

public static String conc(Object a,
                          Object b)

concExc

public static String concExc(Object a,
                             Object b)

currentLine

public int currentLine()

debug_next_token

public Symbol debug_next_token()
            throws java.io.IOException
Same as next_token but also prints the token to standard out for debugging. This code was contributed by Karl Meissner <meissnersd@yahoo.com>

main

public static void main(argv[] )
Runs the scanner on input files. This main method is the debugging routine for the scanner. It prints debugging information about each returned token to System.out until the end of file is reached, or an error occured.
Parameters:

next_token

public Symbol next_token()
            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

setFile

public void setFile(File file)

yybegin

public final void yybegin(int newState)
Enters a new lexical state
Parameters:
newState - the new lexical state

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

yyclose

public final void yyclose()
            throws java.io.IOException
Closes the input stream.

yylength

public final int yylength()
Returns the length of the matched text region.

yymoreStreams

public final boolean yymoreStreams()
Returns true iff there are still streams left to read from on the stream stack.

yypopStream

public final void yypopStream()
            throws java.io.IOException
Closes the current input stream and continues to read from the one on top of the stream stack.

yypushStream

public final void yypushStream(java.io.Reader reader)
Stores the current input stream on a stack, and reads from a new stream. Lexical state, line, char, and column counting remain untouched. The current input stream can be restored with yypopstream (usually in an <<EOF>> action).
Parameters:
reader - the new input stream to read from

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()!

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 ZZ_INITIAL.
Parameters:
reader - the new input stream

yystate

public final int yystate()
Returns the current lexical state.

yytext

public final String yytext()
Returns the text matched by the current regular expression.