package org.hibernate.search.impl;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.apache.lucene.analysis.Analyzer;
import org.apache.solr.analysis.TokenFilterFactory;
import org.apache.solr.analysis.TokenizerChain;
import org.apache.solr.analysis.TokenizerFactory;
import org.apache.solr.common.ResourceLoader;
import org.apache.solr.util.plugin.ResourceLoaderAware;
import org.hibernate.search.SearchException;
import org.hibernate.search.annotations.AnalyzerDef;
import org.hibernate.search.annotations.Parameter;
import org.hibernate.search.annotations.TokenFilterDef;
import org.hibernate.search.annotations.TokenizerDef;
import org.hibernate.search.util.HibernateSearchResourceLoader;
/**
* Instances of this class are used to build Lucene analyzers which are defined using the solr <code>TokenFilterFactory</code>.
* To make the dependency to the solr framework optional only this class has direct dependecies to solr. Solr dependencies
* are not supposed to be used anywhere else (except the actual configuration of the analzers in the domain model).
*
* @author Emmanuel Bernard
* @author Hardy Ferentschik
*/
class SolrAnalyzerBuilder {
private SolrAnalyzerBuilder() {}
/**
* Builds a Lucene <code>Analyzer</code> from the specified <code>AnalyzerDef</code> annotation.
*
* @param analyzerDef The <code>AnalyzerDef</code> annotation as found in the annotated domain class.
* @return a Lucene <code>Analyzer</code>
*/
public static Analyzer buildAnalyzer(AnalyzerDef analyzerDef) {
TokenizerDef token = analyzerDef.tokenizer();
TokenizerFactory tokenFactory = ( TokenizerFactory ) instantiate( token.factory() );
tokenFactory.init( getMapOfParameters( token.params() ) );
final int length = analyzerDef.filters().length;
TokenFilterFactory[] filters = new TokenFilterFactory[length];
ResourceLoader resourceLoader = new HibernateSearchResourceLoader();
for ( int index = 0 ; index < length ; index++ ) {
TokenFilterDef filterDef = analyzerDef.filters()[index];
filters[index] = (TokenFilterFactory) instantiate( filterDef.factory() );
filters[index].init( getMapOfParameters( filterDef.params() ) );
if ( filters[index] instanceof ResourceLoaderAware ) {
((ResourceLoaderAware)filters[index]).inform( resourceLoader );
}
}
return new TokenizerChain(tokenFactory, filters);
}
private static Object instantiate(Class clazz) {
try {
return clazz.newInstance();
}
catch (IllegalAccessException e) {
throw new SearchException( "Unable to instantiate class: " + clazz, e );
}
catch (InstantiationException e) {
throw new SearchException( "Unable to instantiate class: " + clazz, e );
}
}
private static Map<String, String> getMapOfParameters(Parameter[] params) {
Map<String, String> mapOfParams = new HashMap<String, String>( params.length );
for (Parameter param : params) {
mapOfParams.put( param.name(), param.value() );
}
return Collections.unmodifiableMap( mapOfParams );
}
}