bundles/org.simantics.project/src/org/simantics/project/internal/ProjectFeatureRegistry.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.project.internal;
  13
  14 import java.util.ArrayList;
  15 import java.util.Arrays;
  16 import java.util.Collection;
  17 import java.util.HashSet;
  18 import java.util.Set;
  19
  20 import org.eclipse.core.runtime.IConfigurationElement;
  21 import org.eclipse.core.runtime.IExtension;
  22 import org.eclipse.core.runtime.IExtensionPoint;
  23 import org.eclipse.core.runtime.Platform;
  24 import org.eclipse.core.runtime.dynamichelpers.ExtensionTracker;
  25 import org.eclipse.core.runtime.dynamichelpers.IExtensionChangeHandler;
  26 import org.eclipse.core.runtime.dynamichelpers.IExtensionTracker;
  27 import org.eclipse.core.runtime.dynamichelpers.IFilter;
  28 import org.simantics.project.features.registry.GroupReference;
  29 import org.simantics.project.features.registry.IProjectFeatureExtension;
  30 import org.simantics.project.features.registry.IProjectFeatureRegistry;
  31 import org.simantics.project.features.registry.InjectedDependency;
  32 import org.simantics.project.features.registry.ProjectFeatureReference;
  33 import org.simantics.utils.strings.StringUtils;
  34
  35 /**
  36  * This registry implementation is not properly dynamic-enabled.
  37  * injectDependency is not handled well enough to work dynamically.
  38  *
  39  * @author Tuukka Lehtonen
  40  */
  41 public class ProjectFeatureRegistry implements IProjectFeatureRegistry, IExtensionChangeHandler {
  42
  43     private final static String        NAMESPACE         = "org.simantics.project";
  44
  45     private final static String        EP_NAME           = "feature";
  46
  47     private final static String        FEATURE           = "feature";
  48
  49     private final static String        INJECT_DEPENDENCY = "injectDependency";
  50
  51     private final ExtensionTracker     tracker;
  52
  53     private IProjectFeatureExtension[] extensions        = new IProjectFeatureExtension[0];
  54
  55     public ProjectFeatureRegistry() {
  56         tracker = new ExtensionTracker();
  57
  58         // Cache defined actions
  59         IExtensionPoint expt = Platform.getExtensionRegistry().getExtensionPoint(NAMESPACE, EP_NAME);
  60         loadExtensions(expt.getConfigurationElements());
  61
  62         // Start tracking for new and removed extensions
  63         IFilter filter = ExtensionTracker.createExtensionPointFilter(expt);
  64         tracker.registerHandler(this, filter);
  65     }
  66
  67     private void loadExtensions(IConfigurationElement[] configurationElements) {
  68         Set<IProjectFeatureExtension> newExtensions = new HashSet<IProjectFeatureExtension>(Arrays.asList(extensions));
  69
  70         // These are all "feature" elements with required attributes
  71         //  - id
  72         //  - feature
  73         for (IConfigurationElement el : configurationElements) {
  74             if (FEATURE.equals(el.getName())) {
  75                 String id = StringUtils.safeString(el.getAttribute("id"));
  76                 if (ProjectPolicy.TRACE_PROJECT_FEATURE_LOAD)
  77                     System.out.println(this + " Trying to load project feature extension id '" + id + "' contributed by " + el.getContributor().getName());
  78                 if (id.isEmpty()) {
  79                     // Ignore extension without an ID
  80                     // TODO: log warning
  81                     if (ProjectPolicy.TRACE_PROJECT_FEATURE_LOAD)
  82                         System.out.println(this + " skipping feature with empty ID contributed by " + el.getContributor().getName());
  83                     continue;
  84                 }
  85                 if (StringUtils.safeString(el.getAttribute("class")).isEmpty()) {
  86                     // Ignore extension without a feature class
  87                     // TODO: log warning
  88                     if (ProjectPolicy.TRACE_PROJECT_FEATURE_LOAD)
  89                         System.out.println(this + " skipping feature missing 'class' attribute contributed by " + el.getContributor().getName());
  90                     continue;
  91                 }
  92                 // Load optional attributes
  93                 String label = StringUtils.safeString(el.getAttribute("label"));
  94                 String description = StringUtils.safeString(el.getAttribute("description"));
  95                 boolean published = "true".equalsIgnoreCase(el.getAttribute("published"));
  96                 Collection<ProjectFeatureReference> requires = readProjectFeatureReferenceCollection(el, "requires");
  97                 Collection<InjectedDependency> injections = readInjectedDependencies(el);
  98                 Collection<GroupReference> installGroups = readGroupReferenceCollection(el, "installGroup");
  99
 100                 ProjectFeatureExtension ext = new ProjectFeatureExtension(el, id, label, description, published, requires, injections, installGroups);
 101
 102                 // Start tracking the new extension object, its removal will be notified of
 103                 // with removeExtension(extension, Object[]).
 104                 tracker.registerObject(el.getDeclaringExtension(), ext, IExtensionTracker.REF_STRONG);
 105
 106                 newExtensions.add(ext);
 107             }
 108         }
 109
 110         // Atomic assignment
 111         this.extensions = newExtensions.toArray(new IProjectFeatureExtension[newExtensions.size()]);
 112     }
 113
 114     private Collection<InjectedDependency> readInjectedDependencies(IConfigurationElement element) {
 115         Collection<InjectedDependency> result = new ArrayList<InjectedDependency>();
 116
 117         for (IConfigurationElement child : element.getChildren(INJECT_DEPENDENCY)) {
 118             String id = StringUtils.safeString(child.getAttribute("id"));
 119             if (id.isEmpty())
 120                 // Invalid extension
 121                 return null;
 122
 123             String targetId = StringUtils.safeString(child.getAttribute("targetId"));
 124             if (targetId.isEmpty())
 125                 // Invalid extension
 126                 return null;
 127         }
 128
 129         return result;
 130     }
 131
 132     private Collection<ProjectFeatureReference> readProjectFeatureReferenceCollection(IConfigurationElement element, String childName) {
 133         Collection<ProjectFeatureReference> result = new ArrayList<ProjectFeatureReference>();
 134
 135         for (IConfigurationElement child : element.getChildren(childName)) {
 136             String id = StringUtils.safeString(child.getAttribute("id"));
 137             if (id.isEmpty()) {
 138                 // Invalid extension
 139                 continue;
 140             }
 141             boolean optional = "true".equalsIgnoreCase( child.getAttribute("optional") );
 142             result.add(new ProjectFeatureReference(id, optional));
 143         }
 144
 145         return result;
 146     }
 147
 148     private Collection<GroupReference> readGroupReferenceCollection(IConfigurationElement element, String childName) {
 149         Collection<GroupReference> result = new ArrayList<GroupReference>();
 150
 151         for (IConfigurationElement child : element.getChildren(childName)) {
 152             String id = StringUtils.safeString(child.getAttribute("id"));
 153             if (id.isEmpty()) {
 154                 // Invalid extension
 155                 // TODO: log warning
 156                 continue;
 157             }
 158             String version = StringUtils.safeString(child.getAttribute("version"));
 159             if (version.isEmpty())
 160                 // Empty version implies no version, mark that with null.
 161                 version = null;
 162             result.add(new GroupReference(id, version));
 163         }
 164
 165         return result;
 166     }
 167
 168     @Override
 169     public void addExtension(IExtensionTracker tracker, IExtension extension) {
 170         loadExtensions(extension.getConfigurationElements());
 171     }
 172
 173     @Override
 174     public void removeExtension(IExtension extension, Object[] objects) {
 175         Set<IProjectFeatureExtension> newExtensions = new HashSet<IProjectFeatureExtension>(Arrays.asList(extensions));
 176
 177         for (Object o : objects) {
 178             tracker.unregisterObject(extension, o);
 179             newExtensions.remove(o);
 180         }
 181
 182         // Atomic assignment
 183         this.extensions = newExtensions.toArray(new IProjectFeatureExtension[newExtensions.size()]);
 184     }
 185
 186     /* (non-Javadoc)
 187      * @see org.simantics.project.IProjectFeatureRegistry#getExtensions()
 188      */
 189     @Override
 190     public IProjectFeatureExtension[] getExtensions() {
 191         return extensions;
 192     }
 193
 194     @Override
 195     public IProjectFeatureExtension getExtensionById(String id) {
 196         if (id == null)
 197             throw new IllegalArgumentException("null id");
 198
 199         for (IProjectFeatureExtension ext : extensions) {
 200             if (id.equals(ext.getId()))
 201                 return ext;
 202         }
 203         return null;
 204     }
 205
 206 }