bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/predicates/Disjunction.java

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 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.layer0.utils.predicates;
  13
  14 import java.util.Arrays;
  15 import java.util.Collection;
  16 import java.util.Collections;
  17 import java.util.HashSet;
  18 import java.util.Iterator;
  19 import java.util.Set;
  20
  21 import org.simantics.db.Resource;
  22 import org.simantics.db.ReadGraph;
  23 import org.simantics.db.WriteGraph;
  24 import org.simantics.db.exception.DatabaseException;
  25
  26 public class Disjunction extends UnaryPredicate {
  27
  28         Collection<IUnaryPredicate> predicates;
  29
  30         public Disjunction(Collection<IUnaryPredicate> predicates) {
  31                 this.predicates = predicates;
  32         }
  33
  34         public Disjunction(IUnaryPredicate ... predicates) {
  35             this(Arrays.asList(predicates));
  36         }
  37
  38         @Override
  39         public Collection<Resource> getResources(ReadGraph g) throws DatabaseException {
  40                 Iterator<IUnaryPredicate> it = predicates.iterator();
  41
  42                 while(it.hasNext()) {
  43                         Collection<Resource> result = it.next().getResources(g);
  44                         if(!result.isEmpty()) {
  45                                 while(it.hasNext()) {
  46                                         Collection<Resource> temp = it.next().getResources(g);
  47                                         if(!temp.isEmpty()) {
  48                                                 Set<Resource> merged = new HashSet<Resource>(result.size() + temp.size());
  49                                                 merged.addAll(result);
  50                                                 merged.addAll(temp);
  51                                                 while(it.hasNext())
  52                                                         merged.addAll(it.next().getResources(g));
  53                                                 return merged;
  54                                         }
  55                                 }
  56                                 return result;
  57                         }
  58                 }
  59                 return Collections.emptyList();
  60         }
  61
  62         @Override
  63         public boolean has(ReadGraph g, Resource resource) throws DatabaseException {
  64                 for(IUnaryPredicate pred : predicates)
  65                         if(pred.has(g, resource))
  66                                 return true;
  67                 return false;
  68         }
  69
  70         @Override
  71         public boolean supportsUnboundedQuery() {
  72                 for(IUnaryPredicate pred : predicates)
  73                         if(!pred.supportsUnboundedQuery())
  74                                 return false;
  75                 return true;
  76         }
  77
  78         @Override
  79         public void add(WriteGraph g, Resource r) {
  80                 throw new UnsupportedOperationException();
  81         }
  82
  83         @Override
  84         public void remove(WriteGraph g, Resource r) {
  85                 throw new UnsupportedOperationException();
  86         }
  87
  88         @Override
  89         public boolean supportsAddition() {
  90                 return false;
  91         }
  92
  93         @Override
  94         public boolean supportsRemoval() {
  95                 return false;
  96         }
  97
  98         @Override
  99         public int hashCode() {
 100                 final int prime = 31;
 101                 int result = 1;
 102                 result = prime * result
 103                                 + ((predicates == null) ? 0 : predicates.hashCode());
 104                 return result;
 105         }
 106
 107         @Override
 108         public boolean equals(Object obj) {
 109                 if (this == obj)
 110                         return true;
 111                 if (obj == null)
 112                         return false;
 113                 if (getClass() != obj.getClass())
 114                         return false;
 115                 Disjunction other = (Disjunction) obj;
 116                 if (predicates == null) {
 117                         if (other.predicates != null)
 118                                 return false;
 119                 } else if (!predicates.equals(other.predicates))
 120                         return false;
 121                 return true;
 122         }
 123
 124 }