bundles/org.simantics.browsing.ui.graph.impl/src/org/simantics/browsing/ui/graph/impl/GraphViewpointFactory.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.browsing.ui.graph.impl;
  13
  14 import java.util.Collection;
  15
  16 import org.simantics.browsing.ui.BuiltinKeys;
  17 import org.simantics.browsing.ui.NodeContext;
  18 import org.simantics.browsing.ui.PrimitiveQueryUpdater;
  19 import org.simantics.browsing.ui.BuiltinKeys.ViewpointKey;
  20 import org.simantics.browsing.ui.content.Viewpoint;
  21 import org.simantics.browsing.ui.content.ViewpointFactory;
  22 import org.simantics.db.ReadGraph;
  23 import org.simantics.db.Resource;
  24 import org.simantics.db.exception.DatabaseException;
  25
  26 public abstract class GraphViewpointFactory implements ViewpointFactory {
  27
  28     @Override
  29     public Viewpoint create(PrimitiveQueryUpdater updater,
  30             NodeContext context, ViewpointKey key) {
  31         assert(updater != null);
  32         assert(context != null);
  33
  34         return new LazyViewpoint(updater, context, key) {
  35             @Override
  36             public NodeContext[] children(ReadGraph graph) throws DatabaseException {
  37                 return toContextsWithInput(GraphViewpointFactory.this.
  38                         getChildren(graph, (Resource) context.getConstant(BuiltinKeys.INPUT)));
  39             }
  40
  41             @Override
  42             public Boolean hasChildren(ReadGraph graph) throws DatabaseException {
  43                 return children(graph).length > 0;
  44             }
  45
  46             @Override
  47             public String toString() {
  48                 return GraphViewpointFactory.this.toString();
  49             }
  50
  51             @Override
  52             public Object getIdentity() {
  53                 return GraphViewpointFactory.this.getClass();
  54             }
  55
  56         };
  57     }
  58
  59     abstract protected Collection<?> getChildren(ReadGraph g, Resource r) throws DatabaseException;
  60     protected boolean hasChildren(ReadGraph g, Resource r) throws DatabaseException {
  61         return !getChildren(g, r).isEmpty();
  62     }
  63
  64 }