bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/Relation.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.Collection;\r
  15 \r
  16 import org.simantics.db.ReadGraph;\r
  17 import org.simantics.db.Resource;\r
  18 import org.simantics.db.WriteGraph;\r
  19 import org.simantics.db.common.utils.NameUtils;\r
  20 import org.simantics.db.exception.DatabaseException;\r
  21 import org.simantics.utils.datastructures.Pair;\r
  22 \r
  23 public class Relation extends BinaryPredicate {\r
  24 \r
  25         Resource relation;\r
  26         \r
  27         public Relation(Resource relation) {\r
  28                 this.relation = relation;\r
  29         }\r
  30 \r
  31         @Override\r
  32         public Collection<Resource> getObjects(ReadGraph g, Resource subject) throws DatabaseException {\r
  33                 return g.getObjects(subject, relation);\r
  34         }\r
  35 \r
  36         @Override\r
  37         public Collection<Pair<Resource, Resource>> getStatements(ReadGraph g) {\r
  38                 throw new UnsupportedOperationException();\r
  39         }\r
  40 \r
  41         @Override\r
  42         public Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {\r
  43                 return g.getObjects(object, g.getInverse(relation));\r
  44         }\r
  45 \r
  46         @Override\r
  47         public boolean has(ReadGraph g, Resource subject, Resource object) throws DatabaseException {\r
  48                 return g.hasStatement(subject, relation, object);\r
  49         }\r
  50 \r
  51         @Override\r
  52         public boolean supportsGetObjects() {\r
  53                 return true;\r
  54         }\r
  55 \r
  56         @Override\r
  57         public boolean supportsGetStatements() {\r
  58                 return false;\r
  59         }\r
  60 \r
  61         @Override\r
  62         public boolean supportsGetSubjects() {\r
  63                 return true;\r
  64         }\r
  65 \r
  66         @Override\r
  67         public void add(WriteGraph g, Resource subject, Resource object) throws DatabaseException {\r
  68                 g.claim(subject, relation, object);\r
  69         }\r
  70 \r
  71         @Override\r
  72         public void remove(WriteGraph g, Resource subject, Resource object) throws DatabaseException {\r
  73                 g.denyStatement(subject, relation, object);\r
  74         }\r
  75 \r
  76         @Override\r
  77         public boolean supportsAdditions() {\r
  78                 return true;\r
  79         }\r
  80 \r
  81         @Override\r
  82         public boolean supportsRemovals() {\r
  83                 return false;\r
  84         }\r
  85 \r
  86         @Override\r
  87         public int hashCode() {\r
  88                 final int prime = 31;\r
  89                 int result = 1;\r
  90                 result = prime * result\r
  91                                 + ((relation == null) ? 0 : relation.hashCode());\r
  92                 return result;\r
  93         }\r
  94 \r
  95         @Override\r
  96         public boolean equals(Object obj) {\r
  97                 if (this == obj)\r
  98                         return true;\r
  99                 if (obj == null)\r
 100                         return false;\r
 101                 if (getClass() != obj.getClass())\r
 102                         return false;\r
 103                 Relation other = (Relation) obj;\r
 104                 if (relation == null) {\r
 105                         if (other.relation != null)\r
 106                                 return false;\r
 107                 } else if (!relation.equals(other.relation))\r
 108                         return false;\r
 109                 return true;\r
 110         }\r
 111         \r
 112         @Override\r
 113         public IBinaryPredicate inverse(ReadGraph g) throws DatabaseException {\r
 114                 return new Relation(g.getInverse(relation));\r
 115         }\r
 116         \r
 117         @Override\r
 118         public String toString(ReadGraph g) throws DatabaseException {\r
 119                 return NameUtils.getSafeName(g, relation);\r
 120         }\r
 121         \r
 122 }\r