org.apache.lucene.queryParser.ext
Class ParserExtension

java.lang.Object
  org.apache.lucene.queryParser.ext.ParserExtension

public abstract class ParserExtension
extends Object

This class represents an extension base class to the Lucene standard QueryParser. The QueryParser is generated by the JavaCC parser generator. Changing or adding functionality or syntax in the standard query parser requires changes to the JavaCC source file. To enable extending the standard query parser without changing the JavaCC sources and re-generate the parser the ParserExtension can be customized and plugged into an instance of ExtendableQueryParser, a direct subclass of QueryParser.

See Also:

Extensions, ExtendableQueryParser

Constructor Summary

ParserExtension()

Method Summary

abstract Query

parse(ExtensionQuery query) Processes the given ExtensionQuery and returns a corresponding Query instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

ParserExtension

public ParserExtension()

Method Detail

parse

public abstract Query parse(ExtensionQuery query)
                     throws ParseException

Processes the given ExtensionQuery and returns a corresponding Query instance. Subclasses must either return a Query instance or raise a ParseException. This method must not return null.

Parameters:

query - the extension query

Returns:

a new query instance

Throws:

ParseException - if the query can not be parsed.