fr.umlv.tatoo.runtime.parser
Class DefaultParserErrorRecoveryPolicy<T,N,P,V>

java.lang.Object
  fr.umlv.tatoo.runtime.parser.ParserErrorRecoveryPolicy<T,N,P,V>
      fr.umlv.tatoo.runtime.parser.DefaultParserErrorRecoveryPolicy<T,N,P,V>

Type Parameters:

T - type of terminals.

N - type of non-terminals.

P - type of productions.

V - type of versions.

public class DefaultParserErrorRecoveryPolicy<T,N,P,V>
extends ParserErrorRecoveryPolicy<T,N,P,V>

Error recover policy that try to recover ... An instance of this policy must be associated to only one parser because it owns an error state specific to a parser. It use an error recovery listener to inform that during recover phase some terminal or non terminal must be discarded in order to recover.

Author:

Remi Forax, Julien Cervelle

Constructor Summary

DefaultParserErrorRecoveryPolicy(ErrorRecoveryListener<? super T,? super N> errorRecoveryListener)
Creates the recover policy with a listener to signal when pop terminal and non terminal during a recover phase.

Method Summary

boolean	closeParser(Parser<T,N,P,V> parser) Notifies that the parser is closing and an error was notified by ParserErrorRecoveryPolicy.continueRecoverOnError(fr.umlv.tatoo.runtime.parser.Parser, fr.umlv.tatoo.runtime.util.IntArrayList, T) returning ActionReturn.NEXT_ERROR.
ActionReturn	continueRecoverOnError(Parser<T,N,P,V> parser, IntArrayList states, T terminal) Called when error recovery was initiated by recover on error, and method ParserErrorRecoveryPolicy.errorRecoveryNeedsContinuation() returns true
boolean	errorRecoveryNeedsContinuation() Indicate if ParserErrorRecoveryPolicy.continueRecoverOnError(fr.umlv.tatoo.runtime.parser.Parser, fr.umlv.tatoo.runtime.util.IntArrayList, T) needs to be called by processor
Set<? extends T>	getLookahead(Parser<T,N,P,V> parser, Set<? extends T> proposedLookaheads) Returns the lookahead set of terminals that the parser should accept as input of next Parser.step().
ActionReturn	recoverOnError(Parser<T,N,P,V> parser, IntArrayList states, T terminal, String message) Tries to recover on an error.
void	reset() Reset the error recovery policy.

Methods inherited from class fr.umlv.tatoo.runtime.parser.ParserErrorRecoveryPolicy

getNoErrorRecoveryPolicy

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultParserErrorRecoveryPolicy

public DefaultParserErrorRecoveryPolicy(ErrorRecoveryListener<? super T,? super N> errorRecoveryListener)

Creates the recover policy with a listener to signal when pop terminal and non terminal during a recover phase.

Parameters:

errorRecoveryListener - the listener.

Method Detail

recoverOnError

public ActionReturn recoverOnError(Parser<T,N,P,V> parser,
                                   IntArrayList states,
                                   T terminal,
                                   String message)

Description copied from class: ParserErrorRecoveryPolicy

Tries to recover on an error. The method returns true if error recovery started and/or succeeded, false if lexer must skip some input. This method may throw a ParseException to signify a fatal error.

Specified by:

recoverOnError in class ParserErrorRecoveryPolicy<T,N,P,V>

Parameters:

parser - the parser.

states - the state stack of the parser.

terminal - the terminal that caused the error or null if no terminal is available.

Returns:

NEXT if lexer must skip some input.

continueRecoverOnError

public ActionReturn continueRecoverOnError(Parser<T,N,P,V> parser,
                                           IntArrayList states,
                                           T terminal)

Description copied from class: ParserErrorRecoveryPolicy

Called when error recovery was initiated by recover on error, and method ParserErrorRecoveryPolicy.errorRecoveryNeedsContinuation() returns true

Specified by:

continueRecoverOnError in class ParserErrorRecoveryPolicy<T,N,P,V>

Parameters:

parser - the parser.

states - the state stack of the parser.

terminal - current terminal, argument of Parser.step(terminal) or null.

Returns:

NEXT if the terminal must be skipped by the parser, KEEP otherwise.

closeParser

public boolean closeParser(Parser<T,N,P,V> parser)

Description copied from class: ParserErrorRecoveryPolicy

Notifies that the parser is closing and an error was notified by ParserErrorRecoveryPolicy.continueRecoverOnError(fr.umlv.tatoo.runtime.parser.Parser, fr.umlv.tatoo.runtime.util.IntArrayList, T) returning ActionReturn.NEXT_ERROR. This method is called in Parser.close().

Specified by:

closeParser in class ParserErrorRecoveryPolicy<T,N,P,V>

Parameters:

parser - the parser.

Returns:

true if

See Also:

Parser.close()

getLookahead

public Set<? extends T> getLookahead(Parser<T,N,P,V> parser,
                                     Set<? extends T> proposedLookaheads)

Description copied from class: ParserErrorRecoveryPolicy

Returns the lookahead set of terminals that the parser should accept as input of next Parser.step().

Specified by:

getLookahead in class ParserErrorRecoveryPolicy<T,N,P,V>

Parameters:

parser - the parser.

proposedLookaheads - the lookahead set of terminal of current parser state when there is no error.

Returns:

the set of terminals or null for all terminals.

reset

public void reset()

Description copied from class: ParserErrorRecoveryPolicy

Reset the error recovery policy. If the policy maintains some states because it try to recover, they must be reseted.

Specified by:

reset in class ParserErrorRecoveryPolicy<T,N,P,V>

See Also:

Parser.reset(Object)

errorRecoveryNeedsContinuation

public boolean errorRecoveryNeedsContinuation()

Description copied from class: ParserErrorRecoveryPolicy

Indicate if ParserErrorRecoveryPolicy.continueRecoverOnError(fr.umlv.tatoo.runtime.parser.Parser, fr.umlv.tatoo.runtime.util.IntArrayList, T) needs to be called by processor

Specified by:

errorRecoveryNeedsContinuation in class ParserErrorRecoveryPolicy<T,N,P,V>

Returns:

true if ParserErrorRecoveryPolicy.continueRecoverOnError(fr.umlv.tatoo.runtime.parser.Parser, fr.umlv.tatoo.runtime.util.IntArrayList, T) needs to be called by processor