bundles/org.simantics.browsing.ui.model/src/org/simantics/browsing/ui/model/queries/IsNodeContextRemovable.java

   1 /*******************************************************************************
   2  * Copyright (c) 2015 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  *     Semantum Oy - initial API and implementation
  11  *******************************************************************************/
  12 package org.simantics.browsing.ui.model.queries;
  13
  14 import java.util.Collections;
  15
  16 import org.simantics.browsing.ui.BuiltinKeys;
  17 import org.simantics.browsing.ui.NodeContext;
  18 import org.simantics.browsing.ui.model.actions.ActionBrowseContext;
  19 import org.simantics.browsing.ui.model.browsecontexts.ActionBrowseContextRequest;
  20 import org.simantics.db.ReadGraph;
  21 import org.simantics.db.Resource;
  22 import org.simantics.db.common.procedure.adapter.TransientCacheAsyncListener;
  23 import org.simantics.db.common.request.Queries;
  24 import org.simantics.db.common.request.UnaryRead;
  25 import org.simantics.db.exception.DatabaseException;
  26 import org.simantics.db.layer0.adapter.Remover;
  27 import org.simantics.project.ontology.ProjectResource;
  28
  29 /**
  30  * @author Tuukka Lehtonen
  31  * @since 1.18.1
  32  */
  33 public class IsNodeContextRemovable extends UnaryRead<NodeContext, Boolean> {
  34
  35     public IsNodeContextRemovable(NodeContext context) {
  36         super(context);
  37     }
  38
  39     @Override
  40     public Boolean perform(ReadGraph graph) throws DatabaseException {
  41         boolean result = false;
  42         try {
  43             ActionBrowseContext defaultContext = graph.syncRequest(
  44                     new ActionBrowseContextRequest(Collections.singleton(ProjectResource.getInstance(graph).ProjectActionContext)),
  45                     TransientCacheAsyncListener.<ActionBrowseContext>instance());
  46             ActionBrowseContext browseContext = ActionBrowseContext.get(graph, parameter, defaultContext);
  47             if (browseContext != null && !browseContext.canRemove(graph, parameter))
  48                 return false;
  49             result = true;
  50         } catch (DatabaseException e) {
  51             return false;
  52         }
  53
  54         Object input = parameter.getConstant(BuiltinKeys.INPUT);
  55         if (result && input instanceof Resource) {
  56             Remover remover = graph.syncRequest(Queries.adapt((Resource) input, Remover.class, true));
  57             if (remover != null)
  58                 return remover.canRemove(graph, null) == null;
  59         }
  60         return result;
  61     }
  62
  63 }