com.github.chrisbrenton.grappa.parsetree.listeners

Class ParseTreeListener<V>

java.lang.Object

com.github.fge.grappa.run.ParseRunnerListener<V>

com.github.chrisbrenton.grappa.parsetree.listeners.ParseTreeListener<V>

public final class ParseTreeListener<V>
extends com.github.fge.grappa.run.ParseRunnerListener<V>

Parse runner listener used to build a parse tree

This listener will create ParseNodeBuilder instances (for rules annotated with GenerateNode only) and build the parse tree when the user calls getRootNode().

It is required that the root rule have such an annotation (it would be impossible to build a parse tree otherwise); if this is not the case, an IllegalStateException will be thrown (wrapped in a GrappaException).

Also, an attempt to retrieve a parse tree of a failed match will throw an IllegalStateException as well. To prevent this, you should check whether the match is a success (using ParsingResult.isSuccess()) before retrieving the parse tree.

Constructor Summary

Constructors

Constructor and Description
ParseTreeListener(ParseNodeConstructorRepository repository) Constructor

Method Summary

Modifier and Type	Method and Description
void	beforeMatch(com.github.fge.grappa.run.events.PreMatchEvent<V> event)
ParseNode	getRootNode() Get the root ParseNode of the parse tree built by this ParseTreeListener This recursively builds all children, thus building a parse tree.
void	matchFailure(com.github.fge.grappa.run.events.MatchFailureEvent<V> event)
void	matchSuccess(com.github.fge.grappa.run.events.MatchSuccessEvent<V> event)

Methods inherited from class com.github.fge.grappa.run.ParseRunnerListener

afterParse, beforeParse

Methods inherited from class java.lang.Object

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

Constructor Detail

ParseTreeListener

public ParseTreeListener(ParseNodeConstructorRepository repository)

Constructor

Parameters:

repository - the parse node constructors repository

Method Detail

beforeMatch

public void beforeMatch(com.github.fge.grappa.run.events.PreMatchEvent<V> event)

Overrides:

beforeMatch in class com.github.fge.grappa.run.ParseRunnerListener<V>

matchSuccess

public void matchSuccess(com.github.fge.grappa.run.events.MatchSuccessEvent<V> event)

Overrides:

matchSuccess in class com.github.fge.grappa.run.ParseRunnerListener<V>

matchFailure

public void matchFailure(com.github.fge.grappa.run.events.MatchFailureEvent<V> event)

Overrides:

matchFailure in class com.github.fge.grappa.run.ParseRunnerListener<V>

getRootNode

public ParseNode getRootNode()

Get the root ParseNode of the parse tree built by this ParseTreeListener This recursively builds all children, thus building a parse tree.

Returns:

The root node.

Throws:

java.lang.IllegalStateException - Attempt to retrieve the parse tree from a failed match