bundles/org.simantics.ui/src/org/simantics/ui/workbench/ResourceEditorSupport.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2007, 2013 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  *     Semantum Oy - issue #4384\r
  12  *******************************************************************************/\r
  13 package org.simantics.ui.workbench;\r
  14 \r
  15 import org.eclipse.core.runtime.IAdaptable;\r
  16 import org.eclipse.ui.IEditorInput;\r
  17 import org.eclipse.ui.IEditorPart;\r
  18 import org.eclipse.ui.PartInitException;\r
  19 import org.eclipse.ui.PlatformUI;\r
  20 import org.simantics.db.ReadGraph;\r
  21 import org.simantics.db.Session;\r
  22 import org.simantics.db.common.procedure.adapter.ListenerAdapter;\r
  23 import org.simantics.db.common.request.ParametrizedRead;\r
  24 import org.simantics.db.common.request.UnaryRead;\r
  25 import org.simantics.db.event.ChangeEvent;\r
  26 import org.simantics.db.event.ChangeListener;\r
  27 import org.simantics.db.exception.DatabaseException;\r
  28 import org.simantics.db.management.ISessionContext;\r
  29 import org.simantics.db.management.ISessionContextProvider;\r
  30 import org.simantics.db.request.Read;\r
  31 import org.simantics.db.service.GraphChangeListenerSupport;\r
  32 import org.simantics.ui.SimanticsUI;\r
  33 import org.simantics.utils.datastructures.map.Tuple;\r
  34 import org.simantics.utils.ui.ExceptionUtils;\r
  35 import org.simantics.utils.ui.SWTUtils;\r
  36 import org.simantics.utils.ui.workbench.WorkbenchUtils;\r
  37 \r
  38 /**\r
  39  * A helper class for easing the attachment of a Simantics database session to\r
  40  * an editor part.\r
  41  * \r
  42  * It handles the life-cycle of {@link IResourceEditorInput} inputs. It will\r
  43  * listen to graph database changes through {@link ChangeListener} and calls\r
  44  * {@link IResourceEditorInput#update(org.simantics.db.ReadGraph)}.\r
  45  * \r
  46  * Works with any IEditorPart but is only really useful with ones that have\r
  47  * resource inputs.\r
  48  * \r
  49  * @author Tuukka Lehtonen\r
  50  */\r
  51 public class ResourceEditorSupport implements IAdaptable, ChangeListener {\r
  52 \r
  53     private IEditorPart                             editorPart;\r
  54 \r
  55     private ChangeListener                          editorPartChangeListener;\r
  56 \r
  57     private ISessionContext                         sessionContext;\r
  58 \r
  59     // Just a cache to make sure that getSession doesn't NPE.\r
  60     private Session                                 session;\r
  61 \r
  62     ParametrizedRead<IResourceEditorInput, Boolean> inputValidator;\r
  63 \r
  64     private InputListener                           inputListener;\r
  65 \r
  66     public ResourceEditorSupport(IEditorPart editorPart) throws PartInitException {\r
  67         this(editorPart, null);\r
  68     }\r
  69 \r
  70     public ResourceEditorSupport(IEditorPart editorPart, ParametrizedRead<IResourceEditorInput, Boolean> inputValidator) throws PartInitException {\r
  71         this.editorPart = editorPart;\r
  72         this.editorPartChangeListener = getChangeListener(editorPart);\r
  73         this.inputValidator = inputValidator;\r
  74 \r
  75         initSession();\r
  76 \r
  77         IResourceEditorInput input = getResourceInput(editorPart);\r
  78         if (input == null)\r
  79             throw new PartInitException("Editor input must be an IResourceEditorInput, got " + editorPart.getEditorInput());\r
  80 \r
  81         try {\r
  82             input.init(this);\r
  83         } catch (DatabaseException e) {\r
  84             throw new PartInitException("Failed to initialize " + input, e);\r
  85         }\r
  86     }\r
  87 \r
  88     private ISessionContext initSession() throws PartInitException {\r
  89         if (sessionContext == null) {\r
  90             ISessionContextProvider provider = SimanticsUI.getSessionContextProvider();\r
  91             ISessionContext sc = provider.getSessionContext();\r
  92             if (sc == null)\r
  93                 throw new PartInitException("active database session context is null");\r
  94 \r
  95             sessionContext = sc;\r
  96             session = sc.getSession();\r
  97 \r
  98             if (editorPartChangeListener != null) {\r
  99                 GraphChangeListenerSupport support = session.getService(GraphChangeListenerSupport.class);\r
 100                 support.addListener(this);\r
 101             }\r
 102         }\r
 103         return sessionContext;\r
 104     }\r
 105 \r
 106     private ChangeListener getChangeListener(IEditorPart part) {\r
 107         if (part instanceof ChangeListener)\r
 108             return (ChangeListener) part;\r
 109         ChangeListener cl = (ChangeListener) part.getAdapter(ChangeListener.class);\r
 110         return cl;\r
 111     }\r
 112 \r
 113     private static IResourceEditorInput getResourceInput(IEditorPart part) {\r
 114         IEditorInput input = part.getEditorInput();\r
 115         if (input instanceof IResourceEditorInput)\r
 116             return (IResourceEditorInput) input;\r
 117         return null;\r
 118     }\r
 119 \r
 120     public void dispose() {\r
 121         deactivateValidation();\r
 122 \r
 123         // This is special for IResourceInput, has to be done in order not to\r
 124         // leak random access id's for resources.\r
 125         if (!PlatformUI.getWorkbench().isClosing()) {\r
 126             IResourceEditorInput input = getResourceInput(editorPart);\r
 127             if (input != null)\r
 128                 input.dispose();\r
 129         }\r
 130         editorPart = null;\r
 131 \r
 132         sessionContext = null;\r
 133         if (session != null) {\r
 134             if (editorPartChangeListener != null) {\r
 135                 GraphChangeListenerSupport support = session.getService(GraphChangeListenerSupport.class);\r
 136                 support.removeListener(this);\r
 137             }\r
 138             session = null;\r
 139         }\r
 140 \r
 141         editorPartChangeListener = null;\r
 142     }\r
 143 \r
 144     protected boolean isDisposed() {\r
 145         return editorPart == null;\r
 146     }\r
 147 \r
 148     public synchronized void activateValidation() {\r
 149         if (isDisposed())\r
 150             throw new IllegalStateException(this + " is disposed");\r
 151         if (inputListener != null)\r
 152             return;\r
 153 \r
 154         inputListener = new InputListener();\r
 155         getSession().asyncRequest(validationRequest(editorPart), inputListener);\r
 156     }\r
 157 \r
 158     public synchronized void deactivateValidation() {\r
 159         if (isDisposed())\r
 160             throw new IllegalStateException(this + " is disposed");\r
 161         if (inputListener == null)\r
 162             return;\r
 163         inputListener.dispose();\r
 164     }\r
 165 \r
 166     public ISessionContext getSessionContext() {\r
 167         if (sessionContext == null)\r
 168             throw new IllegalStateException("ResourceEditorSupport is disposed");\r
 169         return sessionContext;\r
 170     }\r
 171 \r
 172     public Session getSession() {\r
 173         if (session == null)\r
 174             throw new IllegalStateException("ResourceEditorSupport is disposed");\r
 175         return session;\r
 176     }\r
 177 \r
 178     @SuppressWarnings("rawtypes")\r
 179     @Override\r
 180     public Object getAdapter(Class adapter) {\r
 181         if (adapter == ISessionContext.class)\r
 182             return getSessionContext();\r
 183         if (adapter == Session.class)\r
 184             return getSession();\r
 185         return null;\r
 186     }\r
 187 \r
 188     @Override\r
 189     public void graphChanged(ChangeEvent e) throws DatabaseException {\r
 190         //System.out.println(this + ": graph change: " + e);\r
 191         // Only forward the update to the editor if the input is still valid and\r
 192         // the editor implements ChangeListener\r
 193         if (editorPart instanceof ChangeListener)\r
 194             ((ChangeListener) editorPart).graphChanged(e);\r
 195     }\r
 196 \r
 197     static enum InputState {\r
 198         VALID,\r
 199         INVALID,\r
 200         NON_EXISTENT;\r
 201 \r
 202         public static InputState parse(boolean exists, boolean valid) {\r
 203             if (!exists)\r
 204                 return NON_EXISTENT;\r
 205             return valid ? VALID : INVALID;\r
 206         }\r
 207     }\r
 208 \r
 209     static class Evaluation extends Tuple {\r
 210         public Evaluation(IEditorPart editorPart, IEditorInput input, InputState state, String name, String tooltip) {\r
 211             super(editorPart, input, state, name, tooltip);\r
 212         }\r
 213 \r
 214         public IEditorPart getEditorPart() {\r
 215             return (IEditorPart) getField(0);\r
 216         }\r
 217 \r
 218         public IEditorInput getEditorInput() {\r
 219             return (IEditorInput) getField(1);\r
 220         }\r
 221 \r
 222         public InputState getInputState() {\r
 223             return (InputState) getField(2);\r
 224         }\r
 225     }\r
 226 \r
 227     /**\r
 228      * @param input\r
 229      * @return a read request that returns <code>true</code> for valid inputs\r
 230      *         and <code>false</code> for non-existent or invalid inputs.\r
 231      */\r
 232     private Read<Evaluation> validationRequest(IEditorPart editorPart) {\r
 233         return new UnaryRead<IEditorPart, Evaluation>(editorPart) {\r
 234             @Override\r
 235             public Evaluation perform(ReadGraph graph) throws DatabaseException {\r
 236                 IEditorInput input = parameter.getEditorInput();\r
 237                 IResourceEditorInput resourceInput = getResourceInput(parameter);\r
 238 \r
 239                 //System.out.println(ResourceEditorSupport.this + ": checking input " + input);\r
 240 \r
 241                 boolean exists = true;\r
 242                 boolean valid = true;\r
 243                 if (resourceInput != null) {\r
 244                     exists = resourceInput.exists(graph);\r
 245                     if (exists && inputValidator != null) {\r
 246                         valid = graph.syncRequest(inputValidator.get(resourceInput));\r
 247                     }\r
 248                 } else {\r
 249                     exists = input.exists();\r
 250                 }\r
 251 \r
 252                 InputState state = InputState.parse(exists, valid);\r
 253                 if (state == InputState.VALID) {\r
 254                     // Make sure any cached data in the editor input is up-to-date.\r
 255                     resourceInput.update(graph);\r
 256                 }\r
 257 \r
 258                 Evaluation eval = new Evaluation(parameter, input, state, input.getName(), input.getToolTipText());\r
 259                 //System.out.println(ResourceEditorSupport.this + ": validation evaluation: " + eval);\r
 260                 return eval;\r
 261             }\r
 262         };\r
 263     }\r
 264 \r
 265     private class InputListener extends ListenerAdapter<Evaluation> {\r
 266 \r
 267         private boolean disposed = false;\r
 268 \r
 269         public void dispose() {\r
 270             disposed = true;\r
 271         }\r
 272 \r
 273         @Override\r
 274         public void execute(Evaluation evaluation) {\r
 275             //System.out.println("InputListener: " + evaluation);\r
 276             switch (evaluation.getInputState()) {\r
 277                 case VALID:\r
 278                     break;\r
 279 \r
 280                 case INVALID:\r
 281                 case NON_EXISTENT:\r
 282                     scheduleEditorClose(evaluation.getEditorPart());\r
 283                     break;\r
 284             }\r
 285         }\r
 286 \r
 287         @Override\r
 288         public void exception(Throwable t) {\r
 289             ExceptionUtils.logError("ResourceEditorSupport.InputListener received an unexpected exception.", t);\r
 290         }\r
 291 \r
 292         @Override\r
 293         public boolean isDisposed() {\r
 294             return disposed || ResourceEditorSupport.this.isDisposed();\r
 295         }\r
 296     }\r
 297 \r
 298     private void scheduleEditorClose(final IEditorPart editorPart) {\r
 299         SWTUtils.asyncExec(editorPart.getSite().getShell(), new Runnable() {\r
 300             @Override\r
 301             public void run() {\r
 302                 // Don't have to check isDisposed since closeEditor\r
 303                 // will ignore already closed editor parts.\r
 304                 WorkbenchUtils.closeEditor(editorPart, false);\r
 305             }\r
 306         });\r
 307     }\r
 308 \r
 309 }\r