// $Id: InitContext.java 15532 2008-11-07 16:06:17Z hardy.ferentschik $
package org.hibernate.search.impl;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.search.Similarity;
import org.hibernate.search.Environment;
import org.hibernate.search.SearchException;
import org.hibernate.search.annotations.AnalyzerDef;
import org.hibernate.search.cfg.SearchConfiguration;
import org.hibernate.search.util.DelegateNamedAnalyzer;
import org.hibernate.util.ReflectHelper;
/**
* Provides access to some default configuration settings (eg default <code>Analyzer</code> or default
* <code>Similarity</code>) and checks whether certain optional libraries are available.
*
*
* @author Emmanuel Bernard
* @author Hardy Ferentschik
*/
public class InitContext {
private final Map<String, AnalyzerDef> analyzerDefs = new HashMap<String, AnalyzerDef>();
private final List<DelegateNamedAnalyzer> lazyAnalyzers = new ArrayList<DelegateNamedAnalyzer>();
private final Analyzer defaultAnalyzer;
private final Similarity defaultSimilarity;
private final boolean solrPresent;
private final boolean jpaPresent;
public InitContext(SearchConfiguration cfg) {
defaultAnalyzer = initAnalyzer(cfg);
defaultSimilarity = initSimilarity(cfg);
solrPresent = isPresent( "org.apache.solr.analysis.TokenizerFactory" );
jpaPresent = isPresent( "javax.persistence.Id" );
}
public void addAnalyzerDef(AnalyzerDef ann) {
//FIXME somehow remember where the analyzerDef comes from and raise an exception if an analyzerDef
//with the same name from two different places are added
//multiple adding from the same place is required to deal with inheritance hierarchy processed multiple times
if ( ann != null && analyzerDefs.put( ann.name(), ann ) != null ) {
//throw new SearchException("Multiple AnalyzerDef with the same name: " + name);
}
}
public Analyzer buildLazyAnalyzer(String name) {
final DelegateNamedAnalyzer delegateNamedAnalyzer = new DelegateNamedAnalyzer( name );
lazyAnalyzers.add(delegateNamedAnalyzer);
return delegateNamedAnalyzer;
}
public List<DelegateNamedAnalyzer> getLazyAnalyzers() {
return lazyAnalyzers;
}
/**
* Initializes the Lucene analyzer to use by reading the analyzer class from the configuration and instantiating it.
*
* @param cfg
* The current configuration.
* @return The Lucene analyzer to use for tokenisation.
*/
private Analyzer initAnalyzer(SearchConfiguration cfg) {
Class analyzerClass;
String analyzerClassName = cfg.getProperty( Environment.ANALYZER_CLASS);
if (analyzerClassName != null) {
try {
analyzerClass = ReflectHelper.classForName(analyzerClassName);
} catch (Exception e) {
return buildLazyAnalyzer( analyzerClassName );
}
} else {
analyzerClass = StandardAnalyzer.class;
}
// Initialize analyzer
Analyzer defaultAnalyzer;
try {
defaultAnalyzer = (Analyzer) analyzerClass.newInstance();
} catch (ClassCastException e) {
throw new SearchException("Lucene analyzer does not implement " + Analyzer.class.getName() + ": "
+ analyzerClassName, e);
} catch (Exception e) {
throw new SearchException("Failed to instantiate lucene analyzer with type " + analyzerClassName, e);
}
return defaultAnalyzer;
}
/**
* Initializes the Lucene similarity to use.
*
* @param cfg the search configuration.
* @return returns the default similarity class.
*/
private Similarity initSimilarity(SearchConfiguration cfg) {
Class similarityClass;
String similarityClassName = cfg.getProperty(Environment.SIMILARITY_CLASS);
if (similarityClassName != null) {
try {
similarityClass = ReflectHelper.classForName(similarityClassName);
} catch (Exception e) {
throw new SearchException("Lucene Similarity class '" + similarityClassName + "' defined in property '"
+ Environment.SIMILARITY_CLASS + "' could not be found.", e);
}
}
else {
similarityClass = null;
}
// Initialize similarity
if ( similarityClass == null ) {
return Similarity.getDefault();
}
else {
Similarity defaultSimilarity;
try {
defaultSimilarity = (Similarity) similarityClass.newInstance();
} catch (ClassCastException e) {
throw new SearchException("Lucene similarity does not extend " + Similarity.class.getName() + ": "
+ similarityClassName, e);
} catch (Exception e) {
throw new SearchException("Failed to instantiate lucene similarity with type " + similarityClassName, e);
}
return defaultSimilarity;
}
}
public Analyzer getDefaultAnalyzer() {
return defaultAnalyzer;
}
public Similarity getDefaultSimilarity() {
return defaultSimilarity;
}
public Map<String, Analyzer> initLazyAnalyzers() {
Map<String, Analyzer> initializedAnalyzers = new HashMap<String, Analyzer>( analyzerDefs.size() );
for (DelegateNamedAnalyzer namedAnalyzer : lazyAnalyzers) {
String name = namedAnalyzer.getName();
if ( initializedAnalyzers.containsKey( name ) ) {
namedAnalyzer.setDelegate( initializedAnalyzers.get( name ) );
}
else {
if ( analyzerDefs.containsKey( name ) ) {
final Analyzer analyzer = buildAnalyzer( analyzerDefs.get( name ) );
namedAnalyzer.setDelegate( analyzer );
initializedAnalyzers.put( name, analyzer );
}
else {
throw new SearchException("Analyzer found with an unknown definition: " + name);
}
}
}
//initialize the remaining definitions
for ( Map.Entry<String, AnalyzerDef> entry : analyzerDefs.entrySet() ) {
if ( ! initializedAnalyzers.containsKey( entry.getKey() ) ) {
final Analyzer analyzer = buildAnalyzer( entry.getValue() );
initializedAnalyzers.put( entry.getKey(), analyzer );
}
}
return Collections.unmodifiableMap( initializedAnalyzers );
}
private Analyzer buildAnalyzer(AnalyzerDef analyzerDef) {
if ( ! solrPresent ) {
throw new SearchException( "Use of @AnalyzerDef while Solr is not present in the classpath. Add apache-solr-analyzer.jar" );
}
// SolrAnalyzerBuilder references Solr classes.
// InitContext should not (directly or indirectly) load a Solr class to avoid hard dependency
// unless necessary
// the curent mecanism (check sor class presence and call SolrAnalyzerBuilder if needed
// seems to be sufficient on Apple VM (derived from Sun's
// TODO check on other VMs and be ready for a more reflexive approach
return SolrAnalyzerBuilder.buildAnalyzer( analyzerDef );
}
public boolean isJpaPresent() {
return jpaPresent;
}
private boolean isPresent(String classname) {
try {
ReflectHelper.classForName( classname, InitContext.class );
return true;
}
catch ( Exception e ) {
return false;
}
}
}