bundles/org.simantics.diagram/src/org/simantics/diagram/symbolcontribution/AbstractSymbolProvider.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.diagram.symbolcontribution;
  13
  14 import java.util.Collection;
  15 import java.util.Collections;
  16 import java.util.HashSet;
  17 import java.util.Set;
  18
  19 import org.simantics.diagram.symbollibrary.ISymbolGroup;
  20
  21 public abstract class AbstractSymbolProvider implements ISymbolProvider {
  22     protected volatile boolean         disposed = false;
  23     protected Runnable                 listener;
  24     protected Collection<ISymbolGroup> groups   = Collections.emptyList();
  25     private Set<ISymbolGroup>          groupSet = null;
  26
  27     public Collection<ISymbolGroup> getSymbolGroups() {
  28         return groups;
  29     }
  30
  31     public void setListener(Runnable listener) {
  32         this.listener = listener;
  33     }
  34
  35     public void dispose() {
  36         disposed = true;
  37     }
  38
  39     void setSymbolGroup(Collection<ISymbolGroup> groups) {
  40         if (groups == null)
  41             throw new NullPointerException("null groups");
  42         this.groups = groups;
  43     }
  44
  45     protected Set<ISymbolGroup> getSymbolGroupSet() {
  46         synchronized (this) {
  47             if (groupSet != null)
  48                 return groupSet;
  49             groupSet = new HashSet<ISymbolGroup>(getSymbolGroups());
  50             return groupSet;
  51         }
  52     }
  53
  54     void lockGroups() {
  55         groups = Collections.unmodifiableCollection(groups);
  56         groupSet = null;
  57         getSymbolGroupSet();
  58     }
  59
  60     @Override
  61     public int hashCode() {
  62         return getSymbolGroupSet().hashCode();
  63     }
  64
  65     @Override
  66     public boolean equals(Object obj) {
  67         if (this == obj)
  68             return true;
  69         if (obj == null)
  70             return false;
  71         if (!(obj instanceof AbstractSymbolProvider))
  72             return false;
  73         AbstractSymbolProvider other = (AbstractSymbolProvider) obj;
  74         return getSymbolGroupSet().equals( other.getSymbolGroupSet() );
  75     }
  76
  77 }