bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/predicates/Disjunction.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.predicates;\r
  13 \r
  14 import java.util.Arrays;\r
  15 import java.util.Collection;\r
  16 import java.util.Collections;\r
  17 import java.util.HashSet;\r
  18 import java.util.Iterator;\r
  19 import java.util.Set;\r
  20 \r
  21 import org.simantics.db.Resource;\r
  22 import org.simantics.db.ReadGraph;\r
  23 import org.simantics.db.WriteGraph;\r
  24 import org.simantics.db.exception.DatabaseException;\r
  25 \r
  26 public class Disjunction extends UnaryPredicate {\r
  27 \r
  28         Collection<IUnaryPredicate> predicates;\r
  29 \r
  30         public Disjunction(Collection<IUnaryPredicate> predicates) {\r
  31                 this.predicates = predicates;\r
  32         }\r
  33         \r
  34         public Disjunction(IUnaryPredicate ... predicates) {\r
  35             this(Arrays.asList(predicates));\r
  36         }\r
  37 \r
  38         @Override\r
  39         public Collection<Resource> getResources(ReadGraph g) throws DatabaseException {\r
  40                 Iterator<IUnaryPredicate> it = predicates.iterator();\r
  41                 \r
  42                 while(it.hasNext()) {\r
  43                         Collection<Resource> result = it.next().getResources(g);\r
  44                         if(!result.isEmpty()) {\r
  45                                 while(it.hasNext()) {\r
  46                                         Collection<Resource> temp = it.next().getResources(g);\r
  47                                         if(!temp.isEmpty()) {\r
  48                                                 Set<Resource> merged = new HashSet<Resource>(result.size() + temp.size());\r
  49                                                 merged.addAll(result);\r
  50                                                 merged.addAll(temp);\r
  51                                                 while(it.hasNext())\r
  52                                                         merged.addAll(it.next().getResources(g));\r
  53                                                 return merged;\r
  54                                         }\r
  55                                 }\r
  56                                 return result;\r
  57                         }\r
  58                 }\r
  59                 return Collections.emptyList();\r
  60         }\r
  61     \r
  62         @Override\r
  63         public boolean has(ReadGraph g, Resource resource) throws DatabaseException {\r
  64                 for(IUnaryPredicate pred : predicates)\r
  65                         if(pred.has(g, resource))\r
  66                                 return true;\r
  67                 return false;\r
  68         }\r
  69 \r
  70         @Override\r
  71         public boolean supportsUnboundedQuery() {               \r
  72                 for(IUnaryPredicate pred : predicates)\r
  73                         if(!pred.supportsUnboundedQuery())\r
  74                                 return false;\r
  75                 return true;\r
  76         }\r
  77 \r
  78         @Override\r
  79         public void add(WriteGraph g, Resource r) {\r
  80                 throw new UnsupportedOperationException();\r
  81         }\r
  82 \r
  83         @Override\r
  84         public void remove(WriteGraph g, Resource r) {\r
  85                 throw new UnsupportedOperationException();\r
  86         }\r
  87 \r
  88         @Override\r
  89         public boolean supportsAddition() {\r
  90                 return false;\r
  91         }\r
  92 \r
  93         @Override\r
  94         public boolean supportsRemoval() {              \r
  95                 return false;\r
  96         }\r
  97 \r
  98         @Override\r
  99         public int hashCode() {\r
 100                 final int prime = 31;\r
 101                 int result = 1;\r
 102                 result = prime * result\r
 103                                 + ((predicates == null) ? 0 : predicates.hashCode());\r
 104                 return result;\r
 105         }\r
 106 \r
 107         @Override\r
 108         public boolean equals(Object obj) {\r
 109                 if (this == obj)\r
 110                         return true;\r
 111                 if (obj == null)\r
 112                         return false;\r
 113                 if (getClass() != obj.getClass())\r
 114                         return false;\r
 115                 Disjunction other = (Disjunction) obj;\r
 116                 if (predicates == null) {\r
 117                         if (other.predicates != null)\r
 118                                 return false;\r
 119                 } else if (!predicates.equals(other.predicates))\r
 120                         return false;\r
 121                 return true;\r
 122         }       \r
 123         \r
 124 }\r