bundles/org.simantics.objmap2/src/org/simantics/objmap/graph/rules/range/CollectionAccessor.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2012, 2013 Association for Decentralized Information Management in\r
   3  * 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.objmap.graph.rules.range;\r
  13 \r
  14 import java.lang.reflect.InvocationTargetException;\r
  15 import java.lang.reflect.Method;\r
  16 import java.util.ArrayList;\r
  17 import java.util.Collection;\r
  18 \r
  19 import org.simantics.objmap.exceptions.MappingException;\r
  20 \r
  21 \r
  22 /**\r
  23  * Accessor for mapped collections. \r
  24  * Uses three methods:\r
  25  * - Getter: returns the collection.\r
  26  * - Adder: adds one item into the collection.\r
  27  * - Remover: removes one item from the collection. \r
  28  * \r
  29  * @author Marko Luukkainen <marko.luukkainen@vtt.fi>\r
  30  *\r
  31  * @param <T>\r
  32  */\r
  33 public class CollectionAccessor<Range,T>  implements IRangeAccessor<Range,Collection<T>> {\r
  34         \r
  35         private Method getter;\r
  36         private Method adder;\r
  37         private Method remover;\r
  38         \r
  39         public CollectionAccessor(Method getter, Method adder, Method remover) {\r
  40                 this.getter = getter;\r
  41                 this.adder = adder;\r
  42                 this.remover = remover;\r
  43         }\r
  44         \r
  45         @SuppressWarnings("unchecked")\r
  46         public java.util.Collection<T> get(Object element) throws MappingException {\r
  47                 try {\r
  48                         return (Collection<T>) getter.invoke(element);\r
  49                 } catch (IllegalArgumentException e) {\r
  50                         throw new MappingException(e);\r
  51                 } catch (IllegalAccessException e) {\r
  52                         throw new MappingException(e);\r
  53                 } catch (InvocationTargetException e) {\r
  54                         throw new MappingException(e.getCause());\r
  55                 }\r
  56         };\r
  57 \r
  58         @Override\r
  59         public boolean set(Range element, Collection<T> value)\r
  60                         throws MappingException {\r
  61                 java.util.Collection<T> current = get(element);\r
  62                 Collection<T> adding = new ArrayList<T>();\r
  63                 Collection<T> removing = new ArrayList<T>();\r
  64                 for (T e : current) {\r
  65                         if (!value.contains(e))\r
  66                                 removing.add(e);\r
  67                 }\r
  68                 for (T e : value) {\r
  69                         if (!current.contains(e))\r
  70                                 adding.add(e);\r
  71                 }\r
  72                 \r
  73                 try {\r
  74                         for (T e : removing) {\r
  75                                 remover.invoke(element, e);\r
  76                         }\r
  77                         \r
  78                         for (T e : adding) {\r
  79                                 adder.invoke(element, e);\r
  80                         }\r
  81                 } catch (IllegalArgumentException e) {\r
  82                         throw new MappingException(e);\r
  83                 } catch (IllegalAccessException e) {\r
  84                         throw new MappingException(e);\r
  85                 } catch (InvocationTargetException e) {\r
  86                         throw new MappingException(e.getCause());\r
  87                 }\r
  88                 return removing.size() > 0 || adding.size() > 0;\r
  89                 \r
  90         }\r
  91 }\r