Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.db.common / src / org / simantics / db / common / request / SingleObjectWithType.java

diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/request/SingleObjectWithType.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/request/SingleObjectWithType.java
new file mode 100644 (file)
index 0000000..c2fd2d1
--- /dev/null
+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/request/SingleObjectWithType.java
@@ -0,0 +1,53 @@
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ *     VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.db.common.request;\r
+\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.common.utils.NameUtils;\r
+import org.simantics.db.exception.DatabaseException;\r
+import org.simantics.db.exception.NoSingleResultException;\r
+\r
+/**\r
+ * @author Tuukka Lehtonen\r
+ */\r
+public final class SingleObjectWithType extends ResourceRead3<Resource> {\r
+\r
+    public SingleObjectWithType(Resource resource, Resource predicate, Resource type) {\r
+        super(resource, predicate, type);\r
+    }\r
+\r
+    @Override\r
+    public Resource perform(ReadGraph graph) throws DatabaseException {\r
+        Resource result = null;\r
+        for (Resource object : graph.getObjects(resource, resource2)) {\r
+            if (graph.isInstanceOf(object, resource3)) {\r
+                if (result != null)\r
+                    throw new NoSingleResultException("More than 1 objects for relation "\r
+                            + NameUtils.getSafeName(graph, resource2) + " with type "\r
+                            + NameUtils.getSafeName(graph, resource3) + " at "\r
+                            + NameUtils.getSafeName(graph, resource));\r
+\r
+                result = object;\r
+            }\r
+        }\r
+\r
+        if (result == null)\r
+            throw new NoSingleResultException("No objects for relation "\r
+                    + NameUtils.getSafeName(graph, resource2) + " with type "\r
+                    + NameUtils.getSafeName(graph, resource3) + " at "\r
+                    + NameUtils.getSafeName(graph, resource));\r
+\r
+        return result;\r
+    }\r
+\r
+}\r