bundles/org.simantics.ui/src/org/simantics/ui/workbench/e4/E4ResourceEditorSupport.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.e4;\r
  14 \r
  15 import org.eclipse.ui.PlatformUI;\r
  16 import org.simantics.Simantics;\r
  17 import org.simantics.db.ReadGraph;\r
  18 import org.simantics.db.Resource;\r
  19 import org.simantics.db.common.procedure.adapter.ListenerAdapter;\r
  20 import org.simantics.db.common.request.ParametrizedRead;\r
  21 import org.simantics.db.common.request.TernaryRead;\r
  22 import org.simantics.db.exception.DatabaseException;\r
  23 import org.simantics.ui.workbench.IResourceEditorInput;\r
  24 import org.simantics.utils.datastructures.map.Tuple;\r
  25 import org.simantics.utils.ui.ExceptionUtils;\r
  26 import org.simantics.utils.ui.SWTUtils;\r
  27 \r
  28 /**\r
  29  * A helper class for adding input validation and reaction to input invalidation\r
  30  * to an E4 (editor) part that uses Simantics database {@link Resource}s as its\r
  31  * input.\r
  32  * \r
  33  * <p>\r
  34  * Only useful with E4ResourceEditorBase extending part implementations.\r
  35  * \r
  36  * @author Tuukka Lehtonen\r
  37  */\r
  38 public class E4ResourceEditorSupport {\r
  39 \r
  40     private E4ResourceEditorBase editor;\r
  41 \r
  42     private ParametrizedRead<IResourceEditorInput, Boolean> inputValidator;\r
  43 \r
  44     private InputListener inputListener;\r
  45 \r
  46     public E4ResourceEditorSupport(E4ResourceEditorBase editor) {\r
  47         this(editor, null);\r
  48     }\r
  49 \r
  50     public E4ResourceEditorSupport(E4ResourceEditorBase editor, ParametrizedRead<IResourceEditorInput, Boolean> inputValidator) {\r
  51         this.editor = editor;\r
  52         this.inputValidator = inputValidator;\r
  53     }\r
  54 \r
  55     public void dispose() {\r
  56         deactivateValidation();\r
  57         inputValidator = null;\r
  58         editor = null;\r
  59     }\r
  60 \r
  61     protected boolean isDisposed() {\r
  62         return editor == null;\r
  63     }\r
  64 \r
  65     public synchronized void activateValidation() {\r
  66         if (isDisposed())\r
  67             throw new IllegalStateException(this + " is disposed");\r
  68         if (inputListener != null)\r
  69             return;\r
  70 \r
  71         E4ResourceEditorBase e = editor;\r
  72         inputListener = new InputListener();\r
  73         Simantics.getSession().asyncRequest(new InputEvaluator(e.getPart().getElementId(), e.getResourceInput(), inputValidator), inputListener);\r
  74     }\r
  75 \r
  76     public synchronized void deactivateValidation() {\r
  77         if (isDisposed())\r
  78             throw new IllegalStateException(this + " is disposed");\r
  79         if (inputListener == null)\r
  80             return;\r
  81         inputListener.dispose();\r
  82     }\r
  83 \r
  84     static enum InputState {\r
  85         VALID,\r
  86         INVALID,\r
  87         NON_EXISTENT;\r
  88 \r
  89         public static InputState parse(boolean exists, boolean valid) {\r
  90             if (!exists)\r
  91                 return NON_EXISTENT;\r
  92             return valid ? VALID : INVALID;\r
  93         }\r
  94     }\r
  95 \r
  96     static class Evaluation extends Tuple {\r
  97         public Evaluation(String editorElementId, InputState state) {\r
  98             super(editorElementId, state);\r
  99         }\r
 100 \r
 101         public String getEditorElementId() {\r
 102             return (String) getField(0);\r
 103         }\r
 104 \r
 105         public InputState getInputState() {\r
 106             return (InputState) getField(1);\r
 107         }\r
 108     }\r
 109 \r
 110     public static class InputEvaluator extends TernaryRead<String, IResourceEditorInput, ParametrizedRead<IResourceEditorInput, Boolean>, Evaluation> {\r
 111 \r
 112         public InputEvaluator(String editorElementId, IResourceEditorInput input, ParametrizedRead<IResourceEditorInput, Boolean> inputValidator) {\r
 113             super(editorElementId, input, inputValidator);\r
 114         }\r
 115 \r
 116         @Override\r
 117         public Evaluation perform(ReadGraph graph) throws DatabaseException {\r
 118             //System.out.println(this + ": checking input " + parameter + ", " + parameter2);\r
 119             IResourceEditorInput i = parameter2;\r
 120             boolean exists = i.exists(graph);\r
 121             boolean valid = exists && parameter3 != null\r
 122                     ? graph.syncRequest(parameter3.get(i))\r
 123                     : exists;\r
 124             InputState state = InputState.parse(exists, valid);\r
 125             Evaluation eval = new Evaluation(parameter, state);\r
 126             //System.out.println(this + ": validation evaluation: " + eval);\r
 127             return eval;\r
 128         }\r
 129     }\r
 130 \r
 131     private static class InputListener extends ListenerAdapter<Evaluation> {\r
 132 \r
 133         private boolean disposed = false;\r
 134 \r
 135         public void dispose() {\r
 136             disposed = true;\r
 137         }\r
 138 \r
 139         @Override\r
 140         public void execute(Evaluation evaluation) {\r
 141             //System.out.println("InputListener: " + evaluation);\r
 142             switch (evaluation.getInputState()) {\r
 143                 case VALID:\r
 144                     break;\r
 145 \r
 146                 case INVALID:\r
 147                 case NON_EXISTENT:\r
 148                     scheduleEditorClose(evaluation.getEditorElementId());\r
 149                     break;\r
 150             }\r
 151         }\r
 152 \r
 153         @Override\r
 154         public void exception(Throwable t) {\r
 155             ExceptionUtils.logError("E4ResourceEditorSupport.InputListener received an unexpected exception.", t);\r
 156         }\r
 157 \r
 158         @Override\r
 159         public boolean isDisposed() {\r
 160             return disposed;\r
 161         }\r
 162     }\r
 163 \r
 164     private static void scheduleEditorClose(String editorElementId) {\r
 165         SWTUtils.asyncExec(PlatformUI.getWorkbench().getDisplay(), () -> {\r
 166             E4WorkbenchUtils.closeEditor(editorElementId);\r
 167         });\r
 168     }\r
 169 \r
 170 }\r