bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/predicates/Conjunction.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.ArrayList;
  15 import java.util.Arrays;
  16 import java.util.Collection;
  17
  18 import org.simantics.db.Resource;
  19 import org.simantics.db.ReadGraph;
  20 import org.simantics.db.WriteGraph;
  21 import org.simantics.db.exception.DatabaseException;
  22
  23 public class Conjunction extends UnaryPredicate {
  24
  25         Collection<IUnaryPredicate> predicates;
  26         IUnaryPredicate support;
  27
  28         public Conjunction(Collection<IUnaryPredicate> predicates) {
  29                 for(IUnaryPredicate pred : predicates)
  30                         if(pred.supportsUnboundedQuery()) {
  31                                 this.support = pred;
  32                                 this.predicates = new ArrayList<IUnaryPredicate>(predicates.size()-1);
  33                                 for(IUnaryPredicate pred2 : predicates)
  34                                         if(pred != pred2)
  35                                                 this.predicates.add(pred2);
  36                                 return;
  37                         }
  38                 this.predicates = predicates;
  39                 this.support = null;
  40         }
  41
  42         public Conjunction(IUnaryPredicate ... predicates) {
  43         this(Arrays.asList(predicates));
  44     }
  45
  46         @Override
  47         public Collection<Resource> getResources(ReadGraph g) throws DatabaseException {
  48                 Collection<Resource> result = new ArrayList<Resource>();
  49                 ll:     for(Resource r : support.getResources(g)) {
  50                         for(IUnaryPredicate pred : predicates)
  51                                 if(!pred.has(g, r))
  52                                         continue ll;
  53                         result.add(r);
  54                 }
  55                 return result;
  56         }
  57
  58         @Override
  59         public boolean has(ReadGraph g, Resource resource) throws DatabaseException {
  60                 for(IUnaryPredicate pred : predicates)
  61                         if(!pred.has(g, resource))
  62                                 return false;
  63                 return support == null || support.has(g, resource);
  64         }
  65
  66         @Override
  67         public boolean supportsUnboundedQuery() {
  68                 return support != null;
  69         }
  70
  71         @Override
  72         public void add(WriteGraph g, Resource r) {
  73                 throw new UnsupportedOperationException();
  74         }
  75
  76         @Override
  77         public void remove(WriteGraph g, Resource r) {
  78                 throw new UnsupportedOperationException();
  79         }
  80
  81         @Override
  82         public boolean supportsAddition() {
  83                 return false;
  84         }
  85
  86         @Override
  87         public boolean supportsRemoval() {
  88                 return false;
  89         }
  90
  91         @Override
  92         public int hashCode() {
  93                 final int prime = 31;
  94                 int result = 1;
  95                 result = prime * result
  96                                 + ((predicates == null) ? 0 : predicates.hashCode());
  97                 return result;
  98         }
  99
 100         @Override
 101         public boolean equals(Object obj) {
 102                 if (this == obj)
 103                         return true;
 104                 if (obj == null)
 105                         return false;
 106                 if (getClass() != obj.getClass())
 107                         return false;
 108                 Conjunction other = (Conjunction) obj;
 109                 if (predicates == null) {
 110                         if (other.predicates != null)
 111                                 return false;
 112                 } else if (!predicates.equals(other.predicates))
 113                         return false;
 114                 return true;
 115         }
 116
 117 }