]> gerrit.simantics Code Review - simantics/platform.git/blob - bundles/org.simantics.db.common/src/org/simantics/db/common/request/PossibleStatementWithType.java
Fixed multiple issues causing dangling references to discarded queries
[simantics/platform.git] / bundles / org.simantics.db.common / src / org / simantics / db / common / request / PossibleStatementWithType.java
1 /*******************************************************************************
2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
3  * in Industry THTH ry.
4  * All rights reserved. This program and the accompanying materials
5  * are made available under the terms of the Eclipse Public License v1.0
6  * which accompanies this distribution, and is available at
7  * http://www.eclipse.org/legal/epl-v10.html
8  *
9  * Contributors:
10  *     VTT Technical Research Centre of Finland - initial API and implementation
11  *******************************************************************************/
12 package org.simantics.db.common.request;
13
14 import org.simantics.db.ReadGraph;
15 import org.simantics.db.Resource;
16 import org.simantics.db.Statement;
17 import org.simantics.db.exception.DatabaseException;
18
19 final public class PossibleStatementWithType extends ResourceRead3<Statement> {
20
21     public PossibleStatementWithType(Resource resource, Resource predicate, Resource type) {
22         super(resource, predicate, type);
23     }
24
25     @Override
26     public Statement perform(ReadGraph graph) throws DatabaseException {
27         Statement result = null;
28         for(Statement stm : graph.getStatements(resource, resource2)) {
29             if(graph.isInstanceOf(stm.getObject(), resource3)) {
30                 if(result != null) return null;
31                 result = stm;
32             }
33         }
34         return result;
35     }
36
37 }