bundles/org.simantics.selectionview/src/org/simantics/selectionview/SelectionProcessorBindingExtensionManager.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.selectionview;
  13
  14 import java.util.Arrays;
  15 import java.util.HashSet;
  16 import java.util.Set;
  17
  18 import org.eclipse.core.runtime.CoreException;
  19 import org.eclipse.core.runtime.IConfigurationElement;
  20 import org.eclipse.core.runtime.IExtension;
  21 import org.eclipse.core.runtime.IExtensionPoint;
  22 import org.eclipse.core.runtime.Platform;
  23 import org.eclipse.core.runtime.dynamichelpers.ExtensionTracker;
  24 import org.eclipse.core.runtime.dynamichelpers.IExtensionChangeHandler;
  25 import org.eclipse.core.runtime.dynamichelpers.IExtensionTracker;
  26 import org.eclipse.core.runtime.dynamichelpers.IFilter;
  27 import org.simantics.browsing.ui.common.Activator;
  28 import org.simantics.scl.reflection.OntologyVersions;
  29 import org.simantics.utils.strings.StringUtils;
  30
  31 /**
  32  * @author Tuukka Lehtonen
  33  */
  34 public class SelectionProcessorBindingExtensionManager implements IExtensionChangeHandler {
  35
  36     private final static String                  NAMESPACE  = Activator.PLUGIN_ID;
  37
  38     private final static String                  EP_NAME    = "selectionProcessorBinding";
  39
  40     private ExtensionTracker                     tracker;
  41
  42     private SelectionProcessorBindingExtension[] extensions = new SelectionProcessorBindingExtension[0];
  43
  44     SelectionProcessorBindingExtensionManager() {
  45         tracker = new ExtensionTracker();
  46
  47         // Cache defined actions
  48         IExtensionPoint expt = Platform.getExtensionRegistry().getExtensionPoint(NAMESPACE, EP_NAME);
  49         loadExtensions(expt.getConfigurationElements());
  50
  51         // Start tracking for new and removed extensions
  52         IFilter filter = ExtensionTracker.createExtensionPointFilter(expt);
  53         tracker.registerHandler(this, filter);
  54     }
  55
  56     void close() {
  57         tracker.close();
  58         tracker = null;
  59         extensions = new SelectionProcessorBindingExtension[0];
  60     }
  61
  62     public SelectionProcessorBindingExtension[] getExtensions() {
  63         return extensions;
  64     }
  65
  66     SelectionProcessorReferenceBinding createReferenceBinding(String browseContext, String factoryId) {
  67         return new SelectionProcessorReferenceBinding(browseContext, factoryId);
  68     }
  69
  70
  71     private void loadExtensions(IConfigurationElement[] elements) {
  72
  73         Set<SelectionProcessorBindingExtension> newExtensions = new HashSet<SelectionProcessorBindingExtension>(Arrays.asList(extensions));
  74
  75         for (IConfigurationElement el : elements) {
  76
  77             String browseContext = OntologyVersions.getInstance().currentVersion(StringUtils.safeString(el.getAttribute("browseContext")));
  78
  79             for (IConfigurationElement child : el.getChildren("reference")) {
  80
  81                 String factoryId = StringUtils.safeString(child.getAttribute("id"));
  82                 SelectionProcessorBindingExtension ext = createReferenceBinding(browseContext, factoryId);
  83
  84                 // Start tracking the new extension object, its removal will be notified of
  85                 // with removeExtension(extension, Object[]).
  86                 tracker.registerObject(el.getDeclaringExtension(), ext, IExtensionTracker.REF_STRONG);
  87
  88                 newExtensions.add(ext);
  89
  90             }
  91
  92             for (IConfigurationElement child : el.getChildren("implementation")) {
  93
  94                 try {
  95
  96                     SelectionProcessor<?, ?> processor = (SelectionProcessor<?, ?>) child.createExecutableExtension("class");
  97                     SelectionProcessorBindingExtension ext = new SelectionProcessorImplementationBinding(browseContext, processor);
  98
  99                     // Start tracking the new extension object, its removal will be notified of
 100                     // with removeExtension(extension, Object[]).
 101                     tracker.registerObject(el.getDeclaringExtension(), ext, IExtensionTracker.REF_STRONG);
 102
 103                     newExtensions.add(ext);
 104
 105                 } catch (CoreException e) {
 106
 107                     System.out.println(" == Could not load ViewpointContributionFactory '" + child.getAttribute("class") + "' due to the following error: " + e.getMessage()  );
 108
 109                 }
 110
 111             }
 112
 113         }
 114
 115         // Atomic assignment
 116         this.extensions = newExtensions.toArray(new SelectionProcessorBindingExtension[newExtensions.size()]);
 117     }
 118
 119     @Override
 120     public void addExtension(IExtensionTracker tracker, IExtension extension) {
 121         loadExtensions(extension.getConfigurationElements());
 122     }
 123
 124     @Override
 125     public void removeExtension(IExtension extension, Object[] objects) {
 126         Set<SelectionProcessorBindingExtension> newExtensions = new HashSet<SelectionProcessorBindingExtension>(Arrays.asList(extensions));
 127
 128         for (Object o : objects) {
 129             tracker.unregisterObject(extension, o);
 130             newExtensions.remove(o);
 131         }
 132
 133         // Atomic assignment
 134         this.extensions = newExtensions.toArray(new SelectionProcessorBindingExtension[newExtensions.size()]);
 135     }
 136
 137     public Set<SelectionProcessorBinding> getBoundContributions(Set<String> browseContexts) {
 138         HashSet<SelectionProcessorBinding> result = new HashSet<SelectionProcessorBinding>();
 139
 140         for (SelectionProcessorBindingExtension binding : getExtensions()) {
 141             if (browseContexts.contains(binding.getBrowseContext())) {
 142                 SelectionProcessor<?, ?> processor = binding.getProcessor();
 143                 if (processor != null) {
 144 //                    System.out.println("----------- Plugin contribution " + binding.getFactory());
 145                     result.add(new SelectionProcessorBindingImpl(processor));
 146                 } else {
 147 //                    System.out.println("FAILED: ----------- No factory for " + binding);
 148                 }
 149             }
 150         }
 151
 152         return result;
 153     }
 154
 155     private static SelectionProcessorBindingExtensionManager INSTANCE;
 156
 157     public static synchronized SelectionProcessorBindingExtensionManager getInstance() {
 158         if (INSTANCE == null)
 159             INSTANCE = new SelectionProcessorBindingExtensionManager();
 160         return INSTANCE;
 161     }
 162
 163     public static synchronized void dispose() {
 164         if (INSTANCE != null) {
 165             INSTANCE.close();
 166             INSTANCE = null;
 167         }
 168     }
 169
 170 }