+/*******************************************************************************\r
+ * Copyright (c) 2007, 2013 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ * VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.diagram.participant.e4;\r
+\r
+import java.util.ArrayList;\r
+import java.util.Collection;\r
+import java.util.Collections;\r
+import java.util.HashSet;\r
+import java.util.Set;\r
+\r
+import org.eclipse.e4.ui.services.EContextService;\r
+import org.simantics.g2d.canvas.ICanvasContext;\r
+import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;\r
+import org.simantics.utils.ObjectUtils;\r
+import org.simantics.utils.threads.IThreadWorkQueue;\r
+import org.simantics.utils.threads.ThreadUtils;\r
+\r
+/**\r
+ * ContextUtil manages the activeness of Eclipse Workbench UI context related to\r
+ * an ICanvasContext and an IContextService (possibly local to a workbench part).\r
+ * \r
+ * @author Tuukka Lehtonen\r
+ */\r
+public class ContextUtil extends AbstractCanvasParticipant {\r
+\r
+ private static final boolean DEBUG = false;\r
+\r
+ private final EContextService service;\r
+\r
+ private final IThreadWorkQueue thread;\r
+\r
+ private final Set<String> activations = new HashSet<String>();\r
+\r
+ public ContextUtil(EContextService service, IThreadWorkQueue contextManipulationThread) {\r
+ assert service != null;\r
+ assert contextManipulationThread != null;\r
+ this.service = service;\r
+ this.thread = contextManipulationThread;\r
+ }\r
+\r
+ public void inContextThread(Runnable r) {\r
+ exec(r, true);\r
+ }\r
+\r
+ private void debug(String s) {\r
+ debug(false, s);\r
+ }\r
+\r
+ private void debug(boolean trace, String s) {\r
+ if (DEBUG) {\r
+ System.out.println(getClass().getSimpleName() + "(" + ObjectUtils.hashCode(getContext()) + "): " + s);\r
+ if (trace) {\r
+ StackTraceElement[] es = new Exception().getStackTrace();\r
+ int e = 0;\r
+ System.out.println("Invoked from: ");\r
+ for (int i = 0; i < 2 && e < es.length; ++e) {\r
+ if (es[e].getClassName().equals(getClass().getName()))\r
+ continue;\r
+ System.out.println("\t" + es[e].toString());\r
+ ++i;\r
+ }\r
+ }\r
+ }\r
+ }\r
+\r
+ private void checkThread() {\r
+ if (!thread.currentThreadAccess()) {\r
+ throw new IllegalStateException("not in context thread, use ContextUtil.inContextThread(Runnable)");\r
+ }\r
+ }\r
+\r
+ private void exec(Runnable r) {\r
+ exec(r, false);\r
+ }\r
+\r
+ private void exec(Runnable r, boolean allowSchedule) {\r
+ if (!allowSchedule)\r
+ checkThread();\r
+\r
+ // Context access thread is disposed already?\r
+ if (thread.getThread() == null)\r
+ return;\r
+\r
+ if (thread.currentThreadAccess()) {\r
+ if (DEBUG)\r
+ debug("RUNNING " + r);\r
+ r.run();\r
+ } else {\r
+ if (DEBUG)\r
+ debug("SCHEDULING " + r);\r
+ ThreadUtils.asyncExec(thread, r);\r
+ }\r
+ }\r
+\r
+ @Override\r
+ public void removedFromContext(ICanvasContext ctx) {\r
+ exec(new Runnable() {\r
+ @Override\r
+ public void run() {\r
+ deactivateAll();\r
+ }\r
+ }, true);\r
+ super.removedFromContext(ctx);\r
+ }\r
+\r
+ private void doActivate(String contextId) {\r
+ if(activations.add(contextId)) {\r
+ service.activateContext(contextId);\r
+ if (DEBUG)\r
+ debug("ACTIVATED context: " + contextId);\r
+ } else {\r
+ if (DEBUG)\r
+ debug("TRIED TO ACTIVATE DUPLICATE CONTEXT: " + contextId);\r
+ }\r
+ }\r
+\r
+ public void activate(final String contextId) {\r
+ checkThread();\r
+ if (DEBUG)\r
+ debug(true, "activate(" + contextId + ")");\r
+ assert contextId != null;\r
+ exec(new Runnable() {\r
+ @Override\r
+ public void run() {\r
+ doActivate(contextId);\r
+ }\r
+ });\r
+ }\r
+\r
+ public void activate(final Collection<String> contextIds) {\r
+ if (DEBUG)\r
+ debug(true, "activate contexts (" + contextIds + ")");\r
+ if (contextIds.isEmpty())\r
+ return;\r
+ exec(new Runnable() {\r
+ @Override\r
+ public void run() {\r
+ for (String id : contextIds) {\r
+ doActivate(id);\r
+ }\r
+ }\r
+ });\r
+ }\r
+\r
+ public void deactivate(Collection<String> contextIds) {\r
+ checkThread();\r
+ assert contextIds != null;\r
+ for(String id : contextIds) {\r
+ boolean a = activations.remove(id);\r
+ if (DEBUG)\r
+ debug(true, "deactivate(" + id + "): " + a);\r
+ if (a)\r
+ exec(new Runnable() {\r
+ @Override\r
+ public void run() {\r
+ if (DEBUG)\r
+ debug("DE-ACT context: " + id);\r
+ service.deactivateContext(id);\r
+ }\r
+ });\r
+ }\r
+ }\r
+\r
+ public void deactivateAll() {\r
+ checkThread();\r
+ final Collection<String> contextIds = getActivatedContextIds();\r
+ if (DEBUG)\r
+ debug(true, "DE-ACTIVATE ALL INVOKED, " + contextIds.size() + " contexts to deactivate");\r
+ activations.clear();\r
+ exec(new Runnable() {\r
+ @Override\r
+ public void run() {\r
+ if (DEBUG)\r
+ debug("\tDE-ACTIVATE ALL " + contextIds.size() + " contexts:");\r
+ for (String id : contextIds) {\r
+ if (DEBUG)\r
+ debug("\t\tDE-ACT context: " + id);\r
+ service.deactivateContext(id);\r
+ }\r
+ }\r
+ });\r
+ }\r
+\r
+ public synchronized Collection<String> getActivatedContextIds() {\r
+ return Collections.unmodifiableCollection(new ArrayList<String>(activations));\r
+ }\r
+\r
+}\r