bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/SetUnion2.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.utils.datastructures;
  13
  14 import java.security.InvalidParameterException;
  15 import java.util.Collection;
  16 import java.util.Iterator;
  17 import java.util.List;
  18 import java.util.Set;
  19
  20 public class SetUnion2<T> extends ImmutableCollection<T> {
  21
  22     List<Set<T>> sets;
  23
  24     @Override
  25     public boolean contains(Object o) {
  26         for(Set<T> set : sets)
  27             if(set.contains(o))
  28                 return true;
  29         return false;
  30     }
  31
  32     @Override
  33     public boolean containsAll(Collection<?> c) {
  34         for(Object o : c)
  35             if(!contains(o))
  36                 return false;
  37         return true;
  38     }
  39
  40     @Override
  41     public boolean isEmpty() {
  42         for(Set<T> set : sets)
  43             if(!set.isEmpty())
  44                 return false;
  45         return true;
  46     }
  47
  48     @Override
  49     public Iterator<T> iterator() {
  50         return new ImmutableIterator<T>() {
  51
  52             int setId = 0;
  53             Iterator<T> it = sets.get(0).iterator();
  54             T element = null;
  55
  56             @Override
  57             public boolean hasNext() {
  58                 while(true) {
  59                     if(element != null)
  60                         return true;
  61                     if(it.hasNext()) {
  62                         element = it.next();
  63                         for(int i=0;i<setId;++i)
  64                             if(sets.get(i).contains(element)) {
  65                                 element = null;
  66                                 break;
  67                             }
  68                     }
  69                     else {
  70                         ++setId;
  71                         if(setId < sets.size())
  72                             it = sets.get(setId).iterator();
  73                         else
  74                             return false;
  75                     }
  76                 }
  77             }
  78
  79             @Override
  80             public T next() {
  81                 while(true) {
  82                     if(element != null)
  83                         return element;
  84                     if(it.hasNext()) {
  85                         element = it.next();
  86                         for(int i=0;i<setId;++i)
  87                             if(sets.get(i).contains(element)) {
  88                                 element = null;
  89                                 break;
  90                             }
  91                     }
  92                     else {
  93                         ++setId;
  94                         if(setId < sets.size())
  95                             it = sets.get(setId).iterator();
  96                         else
  97                             throw new InvalidParameterException();
  98                     }
  99                 }
 100             }
 101
 102         };
 103     }
 104
 105     @Override
 106     public int size() {
 107         int count = sets.get(0).size();
 108         for(int i=1;i<sets.size();++i) {
 109             floop:
 110             for(T o : sets.get(i)) {
 111                 for(int j=0;j<i;++j)
 112                     if(sets.get(j).contains(o))
 113                         break floop;
 114                 ++count;
 115             }
 116         }
 117         return count;
 118     }
 119
 120 }