package org.appfuse.dao.hibernate;
import java.util.Collection;
import java.util.HashSet;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.queryParser.MultiFieldQueryParser;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.util.ReaderUtil;
import org.apache.lucene.util.Version;
import org.hibernate.Session;
import org.hibernate.search.FullTextSession;
import org.hibernate.search.MassIndexer;
import org.hibernate.search.Search;
import org.hibernate.search.SearchFactory;
import org.hibernate.search.indexes.IndexReaderAccessor;
/**
* Utility class to generate lucene queries for hibernate search and perform full reindexing.
*
* @author jgarcia
*/
class HibernateSearchTools {
protected static final Log log = LogFactory.getLog(HibernateSearchTools.class);
/**
* Generates a lucene query to search for a given term in all the indexed fields of a class
*
* @param searchTerm the term to search for
* @param searchedEntity the class searched
* @param sess the hibernate session
* @param defaultAnalyzer the default analyzer for parsing the search terms
* @return
* @throws ParseException
*/
public static Query generateQuery(String searchTerm, Class searchedEntity, Session sess, Analyzer defaultAnalyzer) throws ParseException {
Query qry = null;
if (searchTerm.equals("*")) {
qry = new MatchAllDocsQuery();
} else {
// Search in all indexed fields
IndexReaderAccessor readerAccessor = null;
IndexReader reader = null;
try {
FullTextSession txtSession = Search.getFullTextSession(sess);
// obtain analyzer to parse the query:
Analyzer analyzer;
if (searchedEntity == null) {
analyzer = defaultAnalyzer;
} else {
analyzer = txtSession.getSearchFactory().getAnalyzer(searchedEntity);
}
// search on all indexed fields: generate field list, removing internal hibernate search field name: _hibernate_class
// TODO: possible improvement: cache the fields of each entity
SearchFactory searchFactory = txtSession.getSearchFactory();
readerAccessor = searchFactory.getIndexReaderAccessor();
reader = readerAccessor.open(searchedEntity);
Collection<String> fieldNames = new HashSet<>();
for (FieldInfo fieldInfo : ReaderUtil.getMergedFieldInfos(reader)) {
if (fieldInfo.isIndexed) {
fieldNames.add(fieldInfo.name);
}
}
fieldNames.remove("_hibernate_class");
String[] fnames = new String[0];
fnames = fieldNames.toArray(fnames);
// To search on all fields, search the term in all fields
String[] queries = new String[fnames.length];
for (int i = 0; i < queries.length; ++i) {
queries[i] = searchTerm;
}
qry = MultiFieldQueryParser.parse(Version.LUCENE_36, queries, fnames, analyzer);
} finally {
if (readerAccessor != null && reader != null) {
readerAccessor.close(reader);
}
}
}
return qry;
}
/**
* Regenerates the index for a given class
*
* @param clazz the class
* @param sess the hibernate session
*/
public static void reindex(Class clazz, Session sess) {
FullTextSession txtSession = Search.getFullTextSession(sess);
MassIndexer massIndexer = txtSession.createIndexer(clazz);
try {
massIndexer.startAndWait();
} catch (InterruptedException e) {
log.error("mass reindexing interrupted: " + e.getMessage());
} finally {
txtSession.flushToIndexes();
}
}
/**
* Regenerates all the indexed class indexes
*
* @param async true if the reindexing will be done as a background thread
* @param sess the hibernate session
*/
public static void reindexAll(boolean async, Session sess) {
FullTextSession txtSession = Search.getFullTextSession(sess);
MassIndexer massIndexer = txtSession.createIndexer();
massIndexer.purgeAllOnStart(true);
try {
if (!async) {
massIndexer.startAndWait();
} else {
massIndexer.start();
}
} catch (InterruptedException e) {
log.error("mass reindexing interrupted: " + e.getMessage());
} finally {
txtSession.flushToIndexes();
}
}
}