antlr
Class TokenStreamSelector

java.lang.Object
  antlr.TokenStreamSelector

All Implemented Interfaces:

TokenStream

public class TokenStreamSelector

extends java.lang.Object

implements TokenStream

A token stream MUX (multiplexor) knows about n token streams and can multiplex them onto the same channel for use by token stream consumer like a parser. This is a way to have multiple lexers break up the same input stream for a single parser. Or, you can have multiple instances of the same lexer handle multiple input streams; this works great for includes.

Constructor Summary

TokenStreamSelector()

 

Method Summary
void	addInputStream(TokenStream stream, java.lang.String key)
TokenStream	getCurrentStream()           Return the stream from tokens are being pulled at the moment.
TokenStream	getStream(java.lang.String sname)
Token	nextToken()
TokenStream	pop()
void	push(java.lang.String sname)
void	push(TokenStream stream)
void	retry()           Abort recognition of current Token and try again.
void	select(java.lang.String sname)
void	select(TokenStream stream)           Set the stream without pushing old stream

 

Methods inherited from class java.lang.Object

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

 

Constructor Detail

TokenStreamSelector

public TokenStreamSelector()

addInputStream

public void addInputStream(TokenStream stream,
                           java.lang.String key)

getCurrentStream

public TokenStream getCurrentStream()

Return the stream from tokens are being pulled at the moment.

getStream

public TokenStream getStream(java.lang.String sname)

nextToken

public Token nextToken()
                throws TokenStreamException

Specified by:

nextToken in interface TokenStream

Throws:

TokenStreamException

pop

public TokenStream pop()

push

public void push(TokenStream stream)

push

public void push(java.lang.String sname)

retry

public void retry()
           throws TokenStreamRetryException

Abort recognition of current Token and try again. A stream can push a new stream (for include files for example, and then retry(), which will cause the current stream to abort back to this.nextToken(). this.nextToken() then asks for a token from the current stream, which is the new "substream."

Throws:

TokenStreamRetryException

select

public void select(TokenStream stream)

Set the stream without pushing old stream

select

public void select(java.lang.String sname)
            throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException