com.steadystate.css.parser

Class ASCII_CharStream

Implemented Interfaces:
CharStream

public final class ASCII_CharStream
extends java.lang.Object
implements CharStream

An implementation of interface CharStream, where the stream is assumed to contain only ASCII characters (without unicode processing).

Field Summary

int
bufpos
static boolean
staticFlag

Constructor Summary

ASCII_CharStream(java.io.InputStream dstream, int startline, int startcolumn)
ASCII_CharStream(java.io.InputStream dstream, int startline, int startcolumn, int buffersize)
ASCII_CharStream(java.io.Reader dstream, int startline, int startcolumn)
ASCII_CharStream(java.io.Reader dstream, int startline, int startcolumn, int buffersize)

Method Summary

char
BeginToken()
Returns the next character that marks the beginning of the next token.
void
Done()
The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class.
String
GetImage()
Returns a string made up of characters from the marked token beginning to the current buffer position.
char[]
GetSuffix(int len)
Returns an array of characters that make up the suffix of length 'len' for the currently matched token.
void
ReInit(java.io.InputStream dstream, int startline, int startcolumn)
void
ReInit(java.io.InputStream dstream, int startline, int startcolumn, int buffersize)
void
ReInit(java.io.Reader dstream, int startline, int startcolumn)
void
ReInit(java.io.Reader dstream, int startline, int startcolumn, int buffersize)
void
adjustBeginLineColumn(int newLine, int newCol)
Method to adjust line and column numbers for the start of a token.
void
backup(int amount)
Backs up the input stream by amount steps.
int
getBeginColumn()
Returns the column number of the first character for current token (being matched after the last call to BeginTOken).
int
getBeginLine()
Returns the line number of the first character for current token (being matched after the last call to BeginTOken).
int
getColumn()
Deprecated.
int
getEndColumn()
Returns the column number of the last character for current token (being matched after the last call to BeginTOken).
int
getEndLine()
Returns the line number of the last character for current token (being matched after the last call to BeginTOken).
int
getLine()
Deprecated.
char
readChar()
Returns the next character from the selected input.

Field Details

bufpos

public int bufpos

staticFlag

public static final boolean staticFlag
Field Value:
false

Constructor Details

ASCII_CharStream

public ASCII_CharStream(java.io.InputStream dstream,
                        int startline,
                        int startcolumn)

ASCII_CharStream

public ASCII_CharStream(java.io.InputStream dstream,
                        int startline,
                        int startcolumn,
                        int buffersize)

ASCII_CharStream

public ASCII_CharStream(java.io.Reader dstream,
                        int startline,
                        int startcolumn)

ASCII_CharStream

public ASCII_CharStream(java.io.Reader dstream,
                        int startline,
                        int startcolumn,
                        int buffersize)

Method Details

BeginToken

public final char BeginToken()
            throws java.io.IOException
Returns the next character that marks the beginning of the next token. All characters must remain in the buffer between two successive calls to this method to implement backup correctly.
Specified by:
BeginToken in interface CharStream

Done

public void Done()
The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class. Again, the body of this function can be just empty and it will not affect the lexer's operation.
Specified by:
Done in interface CharStream

GetImage

public final String GetImage()
Returns a string made up of characters from the marked token beginning to the current buffer position. Implementations have the choice of returning anything that they want to. For example, for efficiency, one might decide to just return null, which is a valid implementation.
Specified by:
GetImage in interface CharStream

GetSuffix

public final char[] GetSuffix(int len)
Returns an array of characters that make up the suffix of length 'len' for the currently matched token. This is used to build up the matched string for use in actions in the case of MORE. A simple and inefficient implementation of this is as follows : { String t = GetImage(); return t.substring(t.length() - len, t.length()).toCharArray(); }
Specified by:
GetSuffix in interface CharStream

ReInit

public void ReInit(java.io.InputStream dstream,
                   int startline,
                   int startcolumn)

ReInit

public void ReInit(java.io.InputStream dstream,
                   int startline,
                   int startcolumn,
                   int buffersize)

ReInit

public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn)

ReInit

public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn,
                   int buffersize)

adjustBeginLineColumn

public void adjustBeginLineColumn(int newLine,
                                  int newCol)
Method to adjust line and column numbers for the start of a token.

backup

public final void backup(int amount)
Backs up the input stream by amount steps. Lexer calls this method if it had already read some characters, but could not use them to match a (longer) token. So, they will be used again as the prefix of the next token and it is the implemetation's responsibility to do this right.
Specified by:
backup in interface CharStream

getBeginColumn

public final int getBeginColumn()
Returns the column number of the first character for current token (being matched after the last call to BeginTOken).
Specified by:
getBeginColumn in interface CharStream

getBeginLine

public final int getBeginLine()
Returns the line number of the first character for current token (being matched after the last call to BeginTOken).
Specified by:
getBeginLine in interface CharStream

getColumn

public final int getColumn()

Deprecated.

Specified by:
getColumn in interface CharStream

getEndColumn

public final int getEndColumn()
Returns the column number of the last character for current token (being matched after the last call to BeginTOken).
Specified by:
getEndColumn in interface CharStream

getEndLine

public final int getEndLine()
Returns the line number of the last character for current token (being matched after the last call to BeginTOken).
Specified by:
getEndLine in interface CharStream

getLine

public final int getLine()

Deprecated.

Specified by:
getLine in interface CharStream
See Also:
getEndLine()

readChar

public final char readChar()
            throws java.io.IOException
Returns the next character from the selected input. The method of selecting the input is the responsibility of the class implementing this interface. Can throw any java.io.IOException.
Specified by:
readChar in interface CharStream