bundles/org.simantics.objmap2/src/org/simantics/objmap/structural/rules/domain/RelatedObjectAccessor.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2013 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.objmap.structural.rules.domain;
  13
  14 import org.slf4j.Logger;
  15 import org.slf4j.LoggerFactory;
  16 import org.simantics.db.ReadGraph;
  17 import org.simantics.db.Resource;
  18 import org.simantics.db.WriteGraph;
  19 import org.simantics.db.exception.DatabaseException;
  20 import org.simantics.objmap.exceptions.MappingException;
  21 import org.simantics.objmap.graph.rules.domain.IDomainAccessor;
  22 import org.simantics.objmap.structural.StructuralResource;
  23
  24
  25 public class RelatedObjectAccessor implements IDomainAccessor<StructuralResource,StructuralResource> {
  26
  27     static Logger LOGGER = LoggerFactory.getLogger(RelatedObjectAccessor.class);
  28
  29         Resource relation;
  30         boolean useTypeResource;
  31
  32         private boolean preventStructuralChanges = true;
  33         private boolean preventStructuralRootChanges = true;
  34
  35         public RelatedObjectAccessor(Resource relation, boolean useTypeResource) {
  36                 this.relation = relation;
  37                 this.useTypeResource = useTypeResource;
  38         }
  39
  40         public RelatedObjectAccessor(Resource relation, boolean useTypeResource, boolean preventStructuralChanges, boolean preventStructuralRootChanges) {
  41                 this.relation = relation;
  42                 this.useTypeResource = useTypeResource;
  43                 this.preventStructuralChanges = preventStructuralChanges;
  44                 this.preventStructuralRootChanges = preventStructuralRootChanges;
  45         }
  46
  47  private boolean preventChange(StructuralResource element) {
  48         return preventStructuralChanges && element.isStructural() && (!element.isStructuralRoot()||preventStructuralRootChanges);
  49     }
  50
  51         @Override
  52         public StructuralResource get(ReadGraph g, StructuralResource element) throws MappingException {
  53                 try {
  54                     LOGGER.trace("        RelatedObjectAccessor.get");
  55                     Resource res = getServiceResource(g, element);
  56                     if (res == null)
  57                         return null;
  58                         Resource r =  g.getPossibleObject(res, relation);
  59                         if (r == null)
  60                                 return null;
  61                         if (StructuralUtils.isStructuralInstance(g, r)) {
  62                                 return new StructuralResource(g, r, element.getContext(),r);
  63                         } else {
  64                                 return new StructuralResource(g, r, element.getContext());
  65                         }
  66                 } catch (DatabaseException e) {
  67                         throw new MappingException(e);
  68                 }
  69         }
  70
  71         @Override
  72         public boolean set(WriteGraph g, StructuralResource selement, StructuralResource value)
  73                         throws MappingException {
  74                 try {
  75                     LOGGER.trace("        RelatedObjectAccessor.set");
  76                     Resource element = getServiceResource(g, selement);
  77                     if (element == null)
  78                         return false;
  79                     Resource resource = g.getPossibleObject(element, relation);
  80                         if(resource == null) {
  81                             if(value == null)
  82                                 return false;
  83                             if (preventChange(selement))
  84                                         return false;
  85                             g.claim(element, relation, value.getResource());
  86                             return true;
  87                         }
  88                         else if(resource.equals(value.getResource()))
  89                             return false;
  90                         else {
  91                                 if (preventChange(selement))
  92                                         return false;
  93                             g.deny(element, relation);
  94                             if(value != null)
  95                                 g.claim(element, relation, value.getResource());
  96                             return true;
  97                         }
  98                 } catch (DatabaseException e) {
  99                         throw new MappingException(e);
 100                 }
 101
 102         }
 103
 104
 105
 106         private Resource getServiceResource(ReadGraph g, StructuralResource element) {
 107                 if(!useTypeResource)
 108                         return element.getResource();
 109                 return element.getTypeResource();
 110         }
 111
 112 }