bundles/org.simantics.browsing.ui.graph/src/org/simantics/browsing/ui/graph/contributor/viewpoint/ViewpointFactory.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.browsing.ui.graph.contributor.viewpoint;\r
  13 \r
  14 import java.util.Collection;\r
  15 \r
  16 import org.simantics.browsing.ui.BuiltinKeys;\r
  17 import org.simantics.browsing.ui.NodeContext;\r
  18 import org.simantics.browsing.ui.PrimitiveQueryUpdater;\r
  19 import org.simantics.browsing.ui.BuiltinKeys.ViewpointKey;\r
  20 import org.simantics.browsing.ui.content.Viewpoint;\r
  21 import org.simantics.browsing.ui.graph.impl.LazyViewpoint;\r
  22 import org.simantics.db.ReadGraph;\r
  23 import org.simantics.db.exception.DatabaseException;\r
  24 \r
  25 /**\r
  26  * Extend and implement {@link #getChildren(ReadGraph, NodeContext)} to create a\r
  27  * viewpoint factory that reads from the graph database.\r
  28  * \r
  29  * @author Antti Villberg\r
  30  */\r
  31 public abstract class ViewpointFactory<T> implements org.simantics.browsing.ui.content.ViewpointFactory {\r
  32 \r
  33     @Override\r
  34     public Viewpoint create(PrimitiveQueryUpdater updater, NodeContext context, ViewpointKey key) {\r
  35 \r
  36         return new LazyViewpoint(updater, context, key) {\r
  37             @SuppressWarnings("unchecked")\r
  38             @Override\r
  39             public NodeContext[] children(ReadGraph graph) throws DatabaseException {\r
  40 \r
  41                 T input = (T) context.getConstant(BuiltinKeys.INPUT);\r
  42 \r
  43                 return toContextsWithInput(ViewpointFactory.this.\r
  44                         children(graph, input));\r
  45 \r
  46             }\r
  47 \r
  48             @Override\r
  49             public Boolean hasChildren(ReadGraph graph) throws DatabaseException {\r
  50                 return children(graph).length > 0;\r
  51             }\r
  52 \r
  53             @Override\r
  54             public String toString() {\r
  55                 return ViewpointFactory.this.toString();\r
  56             }\r
  57 \r
  58             @Override\r
  59             public Object getIdentity() {\r
  60                 return ViewpointFactory.this.getClass();\r
  61             }\r
  62         };\r
  63 \r
  64     }\r
  65 \r
  66     abstract protected Collection<?> children(ReadGraph g, T input) throws DatabaseException;\r
  67 \r
  68 }\r