bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/OrderedSetElementsPredicate.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.layer0.utils.binaryPredicates;\r
  13 \r
  14 import java.util.ArrayList;\r
  15 import java.util.Collection;\r
  16 import java.util.Collections;\r
  17 \r
  18 import org.simantics.db.ReadGraph;\r
  19 import org.simantics.db.Resource;\r
  20 import org.simantics.db.Statement;\r
  21 import org.simantics.db.WriteGraph;\r
  22 import org.simantics.db.common.utils.OrderedSetUtils;\r
  23 import org.simantics.db.exception.DatabaseException;\r
  24 import org.simantics.layer0.Layer0;\r
  25 import org.simantics.utils.datastructures.Pair;\r
  26 \r
  27 public class OrderedSetElementsPredicate extends BinaryPredicate {\r
  28 \r
  29         public static final OrderedSetElementsPredicate INSTANCE = \r
  30                 new OrderedSetElementsPredicate(); \r
  31         \r
  32         @Override\r
  33         public Collection<Resource> getObjects(ReadGraph g, Resource subject) throws DatabaseException {\r
  34                 Layer0 l0 = Layer0.getInstance(g);\r
  35                 if(g.isInstanceOf(subject, l0.OrderedSet))\r
  36                         return OrderedSetUtils.toList(g, subject);\r
  37                 else\r
  38                         return Collections.emptyList();\r
  39         }\r
  40 \r
  41         @Override\r
  42         public Collection<Pair<Resource, Resource>> getStatements(ReadGraph g) {\r
  43                 throw new UnsupportedOperationException();\r
  44         }\r
  45 \r
  46         @Override\r
  47         public Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {\r
  48                 Collection<Resource> result = new ArrayList<Resource>(1);\r
  49                 Layer0 l0 = Layer0.getInstance(g);\r
  50                 for(Statement stat : g.getStatements(object, l0.IsWeaklyRelatedTo)) {\r
  51                         Resource pred = stat.getPredicate();\r
  52                         if(g.isInstanceOf(pred, l0.OrderedSet) && !pred.equals(object))\r
  53                                 result.add(pred);\r
  54                 }\r
  55                 return result;\r
  56         }\r
  57 \r
  58         @Override\r
  59         public boolean has(ReadGraph g, Resource subject, Resource object) throws DatabaseException {\r
  60                 return OrderedSetUtils.contains(g, subject, object) &&\r
  61                         g.isInstanceOf(subject, Layer0.getInstance(g).OrderedSet);\r
  62         }\r
  63 \r
  64         @Override\r
  65         public boolean supportsGetObjects() {\r
  66                 return true;\r
  67         }\r
  68 \r
  69         @Override\r
  70         public boolean supportsGetStatements() {                \r
  71                 return false;\r
  72         }\r
  73 \r
  74         @Override\r
  75         public boolean supportsGetSubjects() {\r
  76                 return true;\r
  77         }\r
  78 \r
  79         @Override\r
  80         public void add(WriteGraph g, Resource subject, Resource object) throws DatabaseException {\r
  81                 OrderedSetUtils.add(g, subject, object);\r
  82         }\r
  83 \r
  84         @Override\r
  85         public void remove(WriteGraph g, Resource subject, Resource object) throws DatabaseException {\r
  86                 OrderedSetUtils.remove(g, subject, object);\r
  87         }\r
  88 \r
  89         @Override\r
  90         public boolean supportsAdditions() {\r
  91                 return true;\r
  92         }\r
  93 \r
  94         @Override\r
  95         public boolean supportsRemovals() {\r
  96                 return true;\r
  97         }\r
  98         \r
  99 }\r