bundles/org.simantics.g2d/src/org/simantics/g2d/diagram/participant/AbstractDiagramParticipant.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.g2d.diagram.participant;\r
  13 \r
  14 import java.lang.reflect.Field;\r
  15 \r
  16 import org.simantics.g2d.canvas.ICanvasContext;\r
  17 import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;\r
  18 import org.simantics.g2d.canvas.impl.DependencyReflection;\r
  19 import org.simantics.g2d.canvas.impl.DependencyReflection.ReferenceDefinition;\r
  20 import org.simantics.g2d.canvas.impl.DependencyReflection.ReferenceType;\r
  21 import org.simantics.g2d.canvas.impl.HintReflection.HintListener;\r
  22 import org.simantics.g2d.diagram.DiagramClass;\r
  23 import org.simantics.g2d.diagram.DiagramHints;\r
  24 import org.simantics.g2d.diagram.IDiagram;\r
  25 import org.simantics.g2d.diagram.handler.DiagramHandler;\r
  26 import org.simantics.utils.datastructures.hints.IHintObservable;\r
  27 import org.simantics.utils.datastructures.hints.IHintContext.Key;\r
  28 \r
  29 /**\r
  30  * This is a base implementation for all participants that handle\r
  31  * diagram.  \r
  32  * \r
  33  * Features:\r
  34  *  - Overrideable onDiagramSet() method\r
  35  *  - diagram -field points to current diagram\r
  36  *  - DiagramHandlers accessible with @Dependency and @Reference annotations\r
  37  * \r
  38  * TODO add Diagram class handler annotations\r
  39  * @author Toni Kalajainen\r
  40  */\r
  41 public class AbstractDiagramParticipant extends AbstractCanvasParticipant {\r
  42         \r
  43         public IDiagram diagram;\r
  44         public DiagramClass clazz;\r
  45         protected ReferenceDefinition[] handlerDefs;\r
  46         boolean handlerDepsSatisfied = true; \r
  47                 \r
  48         public AbstractDiagramParticipant() {\r
  49                 super();\r
  50                 \r
  51                 handlerDefs = DependencyReflection.getDependencies(this, ReferenceType.DiagramHandler);         \r
  52         }\r
  53         \r
  54         @HintListener(Class=DiagramHints.class, Field="KEY_DIAGRAM")\r
  55         public void hintChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {\r
  56                 if (oldValue==newValue) return;\r
  57                 _setDiagram( (IDiagram) newValue );             \r
  58         }\r
  59         @HintListener(Class=DiagramHints.class, Field="KEY_DIAGRAM")\r
  60         public void hintRemoved(IHintObservable sender, Key key, Object oldValue) {\r
  61                 _setDiagram(null);              \r
  62         }\r
  63 \r
  64         @Override\r
  65         public void addedToContext(ICanvasContext ctx) {\r
  66                 super.addedToContext(ctx);\r
  67                 _setDiagram( (IDiagram) ctx.getHintStack().getHint(DiagramHints.KEY_DIAGRAM) );\r
  68         }\r
  69         \r
  70         @Override\r
  71         public void removedFromContext(ICanvasContext ctx) {\r
  72                 _setDiagram(null);\r
  73                 super.removedFromContext(ctx);\r
  74         }\r
  75         \r
  76         @Override\r
  77         public void assertDependencies() {\r
  78                 super.assertDependencies();\r
  79                 assert(diagram!=null);\r
  80         }\r
  81 \r
  82         private void _setDiagram(IDiagram d)\r
  83         {\r
  84                 IDiagram oldDiagram = this.diagram;\r
  85                 this.diagram = d;\r
  86                 if (d!=null) clazz = d.getDiagramClass();\r
  87                 else clazz=null;\r
  88                 \r
  89                 if (clazz!=null) {\r
  90 \r
  91                         try {\r
  92                                 for (DiagramHandler h : clazz.getAll()) {\r
  93                                         Class<?> c = h.getClass();\r
  94                                         for (ReferenceDefinition def : handlerDefs)\r
  95                                         {\r
  96                                                 Class<?>        defClass = def.requirement;\r
  97                                                 if (!defClass.isAssignableFrom(c)) continue;\r
  98                                                 Field           f = def.field;\r
  99                                                 //Object                value = f.get(this);\r
 100                                                 //assert(value==null);\r
 101                                                 f.set(this, h);\r
 102                                         }\r
 103                                 }\r
 104                         } catch (Exception e) {\r
 105                                 throw new RuntimeException(e);\r
 106                         }               \r
 107                         handlerDepsSatisfied = checkHandlerDependencies();                      \r
 108                 } else {\r
 109 \r
 110                         try {\r
 111                                 for (ReferenceDefinition def : handlerDefs)\r
 112                                 {\r
 113                                         Field           f = def.field;\r
 114                                         f.set(this, null);\r
 115                                 }\r
 116                         } catch (Exception e) {\r
 117                                 throw new RuntimeException(e);\r
 118                         }               \r
 119                         handlerDepsSatisfied = true;\r
 120                 }\r
 121                 onDiagramSet(this.diagram, oldDiagram);\r
 122         }\r
 123         \r
 124         /**\r
 125          * OVERRIDE THIS to hook diagram modifications \r
 126          * @param newDiagram new diagram or null\r
 127          * @param oldDiagram ..\r
 128          */\r
 129         protected void onDiagramSet(IDiagram newDiagram, IDiagram oldDiagram)\r
 130         {\r
 131         }\r
 132         \r
 133         private boolean checkHandlerDependencies() {\r
 134                 try {\r
 135                         for (ReferenceDefinition rd : handlerDefs) {\r
 136                                 if (!rd.dependency)\r
 137                                         continue;\r
 138                                 Field f = rd.field;\r
 139                                 Object o = f.get(this);\r
 140                                 if (o == null)\r
 141                                         return false;\r
 142                         }\r
 143                 } catch (Exception e) {\r
 144                         throw new RuntimeException(e);\r
 145                 }\r
 146                 return true;\r
 147         }       \r
 148 \r
 149         \r
 150         \r
 151 }\r