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