org.antlr.runtime.debug.DebugTokenStream Class Reference

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List of all members.

Public Member Functions

 DebugTokenStream (TokenStream input, DebugEventListener dbg)
void setDebugListener (DebugEventListener dbg)
void consume ()
Token LT (int i)
int LA (int i)
Token get (int i)
int mark ()
int index ()
void rewind (int marker)
void rewind ()
void release (int marker)
void seek (int index)
int size ()
TokenSource getTokenSource ()
String getSourceName ()
String toString ()
String toString (int start, int stop)
String toString (Token start, Token stop)

Public Attributes

TokenStream input

Protected Member Functions

void consumeInitialHiddenTokens ()

Protected Attributes

DebugEventListener dbg
boolean initialStreamState = true
int lastMarker


Detailed Description

Definition at line 32 of file DebugTokenStream.java.


Constructor & Destructor Documentation

org.antlr.runtime.debug.DebugTokenStream.DebugTokenStream ( TokenStream  input,
DebugEventListener  dbg 
)

Definition at line 40 of file DebugTokenStream.java.


Member Function Documentation

void org.antlr.runtime.debug.DebugTokenStream.setDebugListener ( DebugEventListener  dbg  ) 

Definition at line 48 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.consume (  ) 

Implements org.antlr.runtime.IntStream.

Definition at line 52 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.consumeInitialHiddenTokens (  )  [protected]

Definition at line 70 of file DebugTokenStream.java.

Token org.antlr.runtime.debug.DebugTokenStream.LT ( int  k  ) 

Get Token at current input pointer + i ahead where i=1 is next Token. i<0 indicates tokens in the past. So -1 is previous token and -2 is two tokens ago. LT(0) is undefined. For i>=n, return Token.EOFToken. Return null for LT(0) and any index that results in an absolute address that is negative.

Implements org.antlr.runtime.TokenStream.

Definition at line 78 of file DebugTokenStream.java.

int org.antlr.runtime.debug.DebugTokenStream.LA ( int  i  ) 

Get int at current input pointer + i ahead where i=1 is next int. Negative indexes are allowed. LA(-1) is previous token (token just matched). LA(-i) where i is before first token should yield -1, invalid char / EOF.

Implements org.antlr.runtime.IntStream.

Definition at line 86 of file DebugTokenStream.java.

Token org.antlr.runtime.debug.DebugTokenStream.get ( int  i  ) 

Get a token at an absolute index i; 0..n-1. This is really only needed for profiling and debugging and token stream rewriting. If you don't want to buffer up tokens, then this method makes no sense for you. Naturally you can't use the rewrite stream feature. I believe DebugTokenStream can easily be altered to not use this method, removing the dependency.

Implements org.antlr.runtime.TokenStream.

Definition at line 94 of file DebugTokenStream.java.

int org.antlr.runtime.debug.DebugTokenStream.mark (  ) 

Tell the stream to start buffering if it hasn't already. Return current input position, index(), or some other marker so that when passed to rewind() you get back to the same spot. rewind(mark()) should not affect the input cursor. The Lexer track line/col info as well as input index so its markers are not pure input indexes. Same for tree node streams.

Implements org.antlr.runtime.IntStream.

Definition at line 98 of file DebugTokenStream.java.

int org.antlr.runtime.debug.DebugTokenStream.index (  ) 

Return the current input symbol index 0..n where n indicates the last symbol has been read. The index is the symbol about to be read not the most recently read symbol.

Implements org.antlr.runtime.IntStream.

Definition at line 104 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.rewind ( int  marker  ) 

Reset the stream so that next call to index would return marker. The marker will usually be index() but it doesn't have to be. It's just a marker to indicate what state the stream was in. This is essentially calling release() and seek(). If there are markers created after this marker argument, this routine must unroll them like a stack. Assume the state the stream was in when this marker was created.

Implements org.antlr.runtime.IntStream.

Definition at line 108 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.rewind (  ) 

Rewind to the input position of the last marker. Used currently only after a cyclic DFA and just before starting a sem/syn predicate to get the input position back to the start of the decision. Do not "pop" the marker off the state. mark(i) and rewind(i) should balance still. It is like invoking rewind(last marker) but it should not "pop" the marker off. It's like seek(last marker's input position).

Implements org.antlr.runtime.IntStream.

Definition at line 113 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.release ( int  marker  ) 

You may want to commit to a backtrack but don't want to force the stream to keep bookkeeping objects around for a marker that is no longer necessary. This will have the same behavior as rewind() except it releases resources without the backward seek. This must throw away resources for all markers back to the marker argument. So if you're nested 5 levels of mark(), and then release(2) you have to release resources for depths 2..5.

Implements org.antlr.runtime.IntStream.

Definition at line 118 of file DebugTokenStream.java.

void org.antlr.runtime.debug.DebugTokenStream.seek ( int  index  ) 

Set the input cursor to the position indicated by index. This is normally used to seek ahead in the input stream. No buffering is required to do this unless you know your stream will use seek to move backwards such as when backtracking.

This is different from rewind in its multi-directional requirement and in that its argument is strictly an input cursor (index).

For char streams, seeking forward must update the stream state such as line number. For seeking backwards, you will be presumably backtracking using the mark/rewind mechanism that restores state and so this method does not need to update state when seeking backwards.

Currently, this method is only used for efficient backtracking using memoization, but in the future it may be used for incremental parsing.

The index is 0..n-1. A seek to position i means that LA(1) will return the ith symbol. So, seeking to 0 means LA(1) will return the first element in the stream.

Implements org.antlr.runtime.IntStream.

Definition at line 121 of file DebugTokenStream.java.

int org.antlr.runtime.debug.DebugTokenStream.size (  ) 

Only makes sense for streams that buffer everything up probably, but might be useful to display the entire stream or for testing. This value includes a single EOF.

Implements org.antlr.runtime.IntStream.

Definition at line 127 of file DebugTokenStream.java.

TokenSource org.antlr.runtime.debug.DebugTokenStream.getTokenSource (  ) 

Where is this stream pulling tokens from? This is not the name, but the object that provides Token objects.

Implements org.antlr.runtime.TokenStream.

Definition at line 131 of file DebugTokenStream.java.

String org.antlr.runtime.debug.DebugTokenStream.getSourceName (  ) 

Where are you getting symbols from? Normally, implementations will pass the buck all the way to the lexer who can ask its input stream for the file name or whatever.

Implements org.antlr.runtime.IntStream.

Definition at line 135 of file DebugTokenStream.java.

String org.antlr.runtime.debug.DebugTokenStream.toString (  ) 

Definition at line 139 of file DebugTokenStream.java.

String org.antlr.runtime.debug.DebugTokenStream.toString ( int  start,
int  stop 
)

Return the text of all tokens from start to stop, inclusive. If the stream does not buffer all the tokens then it can just return "" or null; Users should not access $ruleLabel.text in an action of course in that case.

Implements org.antlr.runtime.TokenStream.

Definition at line 143 of file DebugTokenStream.java.

String org.antlr.runtime.debug.DebugTokenStream.toString ( Token  start,
Token  stop 
)

Because the user is not required to use a token with an index stored in it, we must provide a means for two token objects themselves to indicate the start/end location. Most often this will just delegate to the other toString(int,int). This is also parallel with the TreeNodeStream.toString(Object,Object).

Implements org.antlr.runtime.TokenStream.

Definition at line 147 of file DebugTokenStream.java.


Member Data Documentation

Definition at line 33 of file DebugTokenStream.java.

Definition at line 34 of file DebugTokenStream.java.

Definition at line 35 of file DebugTokenStream.java.

Track the last mark() call result value for use in rewind().

Definition at line 38 of file DebugTokenStream.java.


The documentation for this class was generated from the following file:

Generated on Wed Oct 1 14:13:44 2008 for ANTLR API by  doxygen 1.5.5