bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/ImmutableSList.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.utils.datastructures;\r
  13 \r
  14 import java.util.Collection;\r
  15 import java.util.Iterator;\r
  16 import java.util.NoSuchElementException;\r
  17 \r
  18 \r
  19 public class ImmutableSList<T> extends ImmutableCollection<T> {\r
  20         \r
  21         final public T                 head;\r
  22         final public ImmutableSList<T> tail; // null, if this is the last element\r
  23         \r
  24         public ImmutableSList(T head, ImmutableSList<T> tail) {\r
  25                 this.head = head;\r
  26                 this.tail = tail;\r
  27         }\r
  28         \r
  29         public ImmutableSList(T head) {\r
  30                 this(head, null);\r
  31         }\r
  32         \r
  33         @Override\r
  34         public boolean contains(Object o) {\r
  35                 ImmutableSList<T> cur = this;\r
  36                 do {\r
  37                         if(cur.head.equals(o))\r
  38                                 return true;\r
  39                         cur = cur.tail;\r
  40                 } while(cur != null);\r
  41                 return false;   \r
  42         }\r
  43         @Override\r
  44         public boolean containsAll(Collection<?> c) {\r
  45                 for(Object o : c)\r
  46                         if(!contains(o))\r
  47                                 return false;\r
  48                 return true;\r
  49         }\r
  50         @Override\r
  51         public boolean isEmpty() {\r
  52                 return false;\r
  53         }\r
  54         \r
  55         static private class Iter<T> implements Iterator<T> {\r
  56                 public ImmutableSList<T> cur;\r
  57                 \r
  58                 public Iter(ImmutableSList<T> cur) {\r
  59                         this.cur = cur;\r
  60                 }\r
  61 \r
  62                 @Override\r
  63                 public boolean hasNext() {\r
  64                         return cur != null;\r
  65                 }\r
  66 \r
  67                 @Override\r
  68                 public T next() {\r
  69                         if(cur == null)\r
  70                                 throw new NoSuchElementException();\r
  71                         T ret = cur.head;\r
  72                         cur = cur.tail;\r
  73                         return ret;\r
  74                 }\r
  75 \r
  76                 @Override\r
  77                 public void remove() {\r
  78                         throw new UnsupportedOperationException();\r
  79                 }\r
  80                 \r
  81         }\r
  82         \r
  83         @Override\r
  84         public Iterator<T> iterator() {\r
  85                 return new Iter<T>(this);\r
  86         }\r
  87         @Override\r
  88         public int size() {\r
  89                 ImmutableSList<T> cur = this;\r
  90                 int count = 0;\r
  91                 do {\r
  92                         ++count;\r
  93                         cur = cur.tail;\r
  94                 } while(cur != null);\r
  95                 return count;   \r
  96         }\r
  97         \r
  98         \r
  99 \r
 100 }\r