/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hp.hpl.jena.sparql.graph;
import java.util.HashSet ;
import java.util.Iterator ;
import java.util.Set ;
import com.hp.hpl.jena.graph.Node ;
import com.hp.hpl.jena.graph.Triple ;
import com.hp.hpl.jena.graph.TripleMatch ;
import com.hp.hpl.jena.graph.impl.SimpleEventManager ;
import com.hp.hpl.jena.graph.query.QueryHandler ;
import com.hp.hpl.jena.graph.query.SimpleQueryHandler ;
import com.hp.hpl.jena.shared.PrefixMapping ;
import com.hp.hpl.jena.shared.impl.PrefixMappingImpl ;
import com.hp.hpl.jena.util.iterator.ClosableIterator ;
import com.hp.hpl.jena.util.iterator.ExtendedIterator ;
import com.hp.hpl.jena.util.iterator.Filter ;
public class GraphMemSimple2 extends GraphBase2
{
private Set<Triple> triples = new HashSet<Triple>() ;
public GraphMemSimple2() {}
@Override
public void performAdd( Triple t )
{ triples.add(t) ; }
@Override
public void performDelete( Triple t )
{ triples.remove(t) ; }
@Override
public QueryHandler queryHandler()
{
return new SimpleQueryHandler(this) ;
}
@Override
protected PrefixMapping createPrefixMapping()
{
return new PrefixMappingImpl() ;
}
@Override
public boolean graphBaseContains( Triple t )
{
if ( t.isConcrete() )
return triples.contains( t ) ;
ClosableIterator<Triple> it = find( t );
try {
for ( ; it.hasNext() ; )
{
Triple t2 = it.next() ;
if ( tripleContained(t, t2) )
return true ;
}
} finally { it.close(); }
return false ;
}
@Override
protected ExtendedIterator<Triple> graphBaseFind(TripleMatch m)
{
Iterator<Triple> iter = triples.iterator() ;
return
SimpleEventManager.notifyingRemove( this, iter )
.filterKeep ( new TripleMatchFilterEquality( m.asTriple() ) );
}
static boolean tripleContained(Triple patternTriple, Triple dataTriple)
{
return
equalNode(patternTriple.getSubject(), dataTriple.getSubject()) &&
equalNode(patternTriple.getPredicate(), dataTriple.getPredicate()) &&
equalNode(patternTriple.getObject(), dataTriple.getObject()) ;
}
private static boolean equalNode(Node m, Node n)
{
// m should not be null unless .getMatchXXXX used to get the node.
// Language tag canonicalization
n = fixupNode(n) ;
m = fixupNode(m) ;
return (m==null) || (m == Node.ANY) || m.equals(n) ;
}
private static Node fixupNode(Node node)
{
if ( node == null || node == Node.ANY )
return node ;
// RDF says ... language tags should be canonicalized to lower case.
if ( node.isLiteral() )
{
String lang = node.getLiteralLanguage() ;
if ( lang != null && ! lang.equals("") )
node = Node.createLiteral(node.getLiteralLexicalForm(),
lang.toLowerCase(),
node.getLiteralDatatype()) ;
}
return node ;
}
static class TripleMatchFilterEquality extends Filter<Triple>
{
final protected Triple tMatch;
/** Creates new TripleMatchFilter */
public TripleMatchFilterEquality(Triple tMatch)
{ this.tMatch = tMatch; }
@Override
public boolean accept(Triple t)
{
return tripleContained(tMatch, t) ;
}
}
}