org.eaglei.lexical.lucene
Class LuceneUtils

java.lang.Object
  org.eaglei.lexical.lucene.LuceneUtils

public class LuceneUtils
extends java.lang.Object

Lucene utility code.

Author:

rfrost

Constructor Summary

LuceneUtils()

Method Summary

static org.apache.lucene.search.Query	escapeIfInvalid(org.apache.lucene.queryParser.QueryParser parser, java.lang.String query) Attempts to parse the specified query string using the specified QueryParser.
static org.apache.lucene.search.Query	rewriteToFuzzy(org.apache.lucene.search.Query originalQuery) Rewrites the specified Query to a form where all contained Terms have the "fuzzy" modifier (Levenstein edit distance) Only rewrites queries that are: BooleanQueries if any clause is more complex than a term or phrase, it is skipped if any clause has the NOT modifier, skip TermQueries

Methods inherited from class java.lang.Object

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

Constructor Detail

LuceneUtils

public LuceneUtils()

Method Detail

escapeIfInvalid

public static org.apache.lucene.search.Query escapeIfInvalid(org.apache.lucene.queryParser.QueryParser parser,
                                                             java.lang.String query)
                                                      throws org.apache.lucene.queryParser.ParseException

Attempts to parse the specified query string using the specified QueryParser. If a parsing error is encountered, invalid syntax is escaped and the parse is attempted again.

Parameters:

parser - The QueryParser.

query - The query string

Returns:

Query

Throws:

org.apache.lucene.queryParser.ParseException - Parse exception generated after escaping special syntax.

rewriteToFuzzy

public static org.apache.lucene.search.Query rewriteToFuzzy(org.apache.lucene.search.Query originalQuery)

Rewrites the specified Query to a form where all contained Terms have the "fuzzy" modifier (Levenstein edit distance) Only rewrites queries that are:

• BooleanQueries
  • if any clause is more complex than a term or phrase, it is skipped
  • if any clause has the NOT modifier, skip
• TermQueries

Parameters:

originalQuery -

Returns:

Query with child TermQueries rewritten as FuzzyQueries.