org.antlr.runtime.debug
Class DebugParser

java.lang.Object
  org.antlr.runtime.BaseRecognizer
      org.antlr.runtime.Parser
          org.antlr.runtime.debug.DebugParser

public class DebugParser
extends Parser

Field Summary

protected DebugEventListener	dbg Who to notify when events in the parser occur.
boolean	isCyclicDecision Used to differentiate between fixed lookahead and cyclic DFA decisions while profiling.

Fields inherited from class org.antlr.runtime.Parser

input

Fields inherited from class org.antlr.runtime.BaseRecognizer

_fsp, backtracking, DEFAULT_TOKEN_CHANNEL, errorRecovery, failed, following, HIDDEN, INITIAL_FOLLOW_STACK_SIZE, lastErrorIndex, MEMO_RULE_FAILED, MEMO_RULE_FAILED_I, MEMO_RULE_UNKNOWN, NEXT_TOKEN_RULE_NAME, ruleMemo

Constructor Summary

DebugParser(TokenStream input)

DebugParser(TokenStream input, DebugEventListener dbg)
Create a normal parser except wrap the token stream in a debug proxy that fires consume events.

DebugParser(TokenStream input, int port)
Create a proxy to marshall events across socket to another listener.

Method Summary

void	beginBacktrack(int level)
void	beginResync() A hook to listen in on the token consumption during error recovery.
void	endBacktrack(int level, boolean successful)
void	endResync()
DebugEventListener	getDebugListener()
void	recoverFromMismatchedSet(IntStream input, RecognitionException mte, BitSet follow)
void	recoverFromMismatchedToken(IntStream input, RecognitionException mte, int ttype, BitSet follow) Attempt to recover from a single missing or extra token.
void	reportError(java.io.IOException e)
void	setDebugListener(DebugEventListener dbg) Provide a new debug event listener for this parser.

Methods inherited from class org.antlr.runtime.Parser

getTokenStream, reset, setTokenStream, traceIn, traceOut

Methods inherited from class org.antlr.runtime.BaseRecognizer

alreadyParsedRule, combineFollows, computeContextSensitiveRuleFOLLOW, computeErrorRecoverySet, consumeUntil, consumeUntil, displayRecognitionError, emitErrorMessage, getBacktrackingLevel, getErrorHeader, getErrorMessage, getGrammarFileName, getRuleInvocationStack, getRuleInvocationStack, getRuleMemoization, getRuleMemoizationCacheSize, getTokenErrorDisplay, getTokenNames, match, matchAny, memoize, mismatch, pushFollow, recover, recoverFromMismatchedElement, reportError, toStrings, traceIn, traceOut

Methods inherited from class java.lang.Object

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

Field Detail

dbg

protected DebugEventListener dbg

Who to notify when events in the parser occur.

isCyclicDecision

public boolean isCyclicDecision

Used to differentiate between fixed lookahead and cyclic DFA decisions while profiling.

Constructor Detail

DebugParser

public DebugParser(TokenStream input,
                   DebugEventListener dbg)

Create a normal parser except wrap the token stream in a debug proxy that fires consume events.

DebugParser

public DebugParser(TokenStream input)

DebugParser

public DebugParser(TokenStream input,
                   int port)

Create a proxy to marshall events across socket to another listener. This constructor returns after handshaking with debugger so programmer does not have to manually invoke handshake.

Method Detail

setDebugListener

public void setDebugListener(DebugEventListener dbg)

Provide a new debug event listener for this parser. Notify the input stream too that it should send events to this listener.

getDebugListener

public DebugEventListener getDebugListener()

reportError

public void reportError(java.io.IOException e)

beginResync

public void beginResync()

Description copied from class: BaseRecognizer

A hook to listen in on the token consumption during error recovery. The DebugParser subclasses this to fire events to the listenter.

Overrides:

beginResync in class BaseRecognizer

endResync

public void endResync()

Overrides:

endResync in class BaseRecognizer

beginBacktrack

public void beginBacktrack(int level)

endBacktrack

public void endBacktrack(int level,
                         boolean successful)

recoverFromMismatchedToken

public void recoverFromMismatchedToken(IntStream input,
                                       RecognitionException mte,
                                       int ttype,
                                       BitSet follow)
                                throws RecognitionException

Description copied from class: BaseRecognizer

Attempt to recover from a single missing or extra token. EXTRA TOKEN LA(1) is not what we are looking for. If LA(2) has the right token, however, then assume LA(1) is some extra spurious token. Delete it and LA(2) as if we were doing a normal match(), which advances the input. MISSING TOKEN If current token is consistent with what could come after ttype then it is ok to "insert" the missing token, else throw exception For example, Input "i=(3;" is clearly missing the ')'. When the parser returns from the nested call to expr, it will have call chain: stat -> expr -> atom and it will be trying to match the ')' at this point in the derivation: => ID '=' '(' INT ')' ('+' atom)* ';' ^ match() will see that ';' doesn't match ')' and report a mismatched token error. To recover, it sees that LA(1)==';' is in the set of tokens that can follow the ')' token reference in rule atom. It can assume that you forgot the ')'.

Overrides:

recoverFromMismatchedToken in class BaseRecognizer

Throws:

RecognitionException

recoverFromMismatchedSet

public void recoverFromMismatchedSet(IntStream input,
                                     RecognitionException mte,
                                     BitSet follow)
                              throws RecognitionException

Overrides:

recoverFromMismatchedSet in class BaseRecognizer

Throws:

RecognitionException