1 /*******************************************************************************
2 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
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
10 * VTT Technical Research Centre of Finland - initial API and implementation
11 *******************************************************************************/
12 package org.simantics.browsing.ui.graph.impl;
14 import java.util.Collection;
16 import org.simantics.browsing.ui.NodeContext;
17 import org.simantics.browsing.ui.PrimitiveQueryUpdater;
18 import org.simantics.browsing.ui.BuiltinKeys.ViewpointKey;
19 import org.simantics.browsing.ui.content.Viewpoint;
20 import org.simantics.browsing.ui.content.ViewpointFactory;
21 import org.simantics.db.ReadGraph;
22 import org.simantics.db.exception.DatabaseException;
25 * Extend and implement {@link #getChildren(ReadGraph, NodeContext)} to create a
26 * viewpoint factory that reads from the graph database.
28 * @author Antti Villberg
30 public abstract class LazyViewpointFactory implements ViewpointFactory {
33 public Viewpoint create(PrimitiveQueryUpdater updater,
34 NodeContext context, ViewpointKey key) {
35 return new LazyViewpoint(updater, context, key) {
37 public NodeContext[] children(ReadGraph graph) throws DatabaseException {
38 return toContextsWithInput(LazyViewpointFactory.this.
39 getChildren(graph, context));
43 public Boolean hasChildren(ReadGraph graph) throws DatabaseException {
44 return children(graph).length > 0;
48 public String toString() {
49 return LazyViewpointFactory.this.toString();
53 public Object getIdentity() {
54 return LazyViewpointFactory.this.getClass();
59 abstract protected Collection<?> getChildren(ReadGraph g, NodeContext context) throws DatabaseException;
61 protected boolean hasChildren(ReadGraph g, NodeContext context) throws DatabaseException {
62 return !getChildren(g, context).isEmpty();