antlr

Class TokenStreamCopyingHiddenTokenFilter

java.lang.Object

antlr.TokenStreamBasicFilter

antlr.TokenStreamHiddenTokenFilter

antlr.TokenStreamCopyingHiddenTokenFilter

All Implemented Interfaces:

antlr.ASdebug.IASDebugStream, antlr.TokenStream

public class TokenStreamCopyingHiddenTokenFilter
extends antlr.TokenStreamHiddenTokenFilter
implements antlr.TokenStream

This class provides TokenStreamHiddenTokenFilters with the concept of tokens which can be copied so that they are seen by both the hidden token stream as well as the parser itself. This is useful when one wants to use an existing parser (like the Java parser included with ANTLR) that throws away some tokens to create a parse tree which can be used to spit out a copy of the code with only minor modifications. This code is partially derived from the public domain ANLTR TokenStream

Field Summary

Fields

Modifier and Type	Field and Description
protected antlr.collections.impl.BitSet	copyMask

Fields inherited from class antlr.TokenStreamHiddenTokenFilter

firstHidden, hideMask, lastHiddenToken, nextMonitoredToken

Fields inherited from class antlr.TokenStreamBasicFilter

discardMask, input

Constructor Summary

Constructors

Constructor and Description
TokenStreamCopyingHiddenTokenFilter(antlr.TokenStream input)

Method Summary

Modifier and Type	Method and Description
void	copy(int tokenType) Indicate that all tokens of type tokenType should be copied.
void	linkAndCopyToken(antlr.CommonHiddenStreamToken prev, antlr.CommonHiddenStreamToken monitored)
antlr.Token	nextToken() Return the next monitored token.
antlr.CommonHiddenStreamToken	partialCloneToken(antlr.CommonHiddenStreamToken t) Create a clone of the important parts of the given token.

Methods inherited from class antlr.TokenStreamHiddenTokenFilter

consume, getDiscardMask, getHiddenAfter, getHiddenBefore, getHideMask, getInitialHiddenToken, hide, hide, LA

Methods inherited from class antlr.TokenStreamBasicFilter

discard, discard, getEntireText, getOffsetInfo

Methods inherited from class java.lang.Object

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

Field Detail

copyMask

protected antlr.collections.impl.BitSet copyMask

Constructor Detail

TokenStreamCopyingHiddenTokenFilter

public TokenStreamCopyingHiddenTokenFilter(antlr.TokenStream input)

Method Detail

copy

public void copy(int tokenType)

Indicate that all tokens of type tokenType should be copied. The copy is put in the stream of hidden tokens, and the original is returned in the stream of normal tokens.

Parameters:

tokenType - integer representing the token type to copied

partialCloneToken

public antlr.CommonHiddenStreamToken partialCloneToken(antlr.CommonHiddenStreamToken t)

Create a clone of the important parts of the given token. Note that this does NOT copy the hiddenBefore and hiddenAfter fields.

Parameters:

t - token to partially clone

Returns:

newly created partial clone

linkAndCopyToken

public void linkAndCopyToken(antlr.CommonHiddenStreamToken prev,
                             antlr.CommonHiddenStreamToken monitored)

nextToken

public antlr.Token nextToken()
                      throws antlr.TokenStreamException

Return the next monitored token. Test the token following the monitored token. If following is another monitored token, save it for the next invocation of nextToken (like a single lookahead token) and return it then. If following is unmonitored, nondiscarded (hidden) channel token, add it to the monitored token. Note: EOF must be a monitored Token.

Specified by:

nextToken in interface antlr.TokenStream

Overrides:

nextToken in class antlr.TokenStreamHiddenTokenFilter

Throws:

antlr.TokenStreamException