--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 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
+\r
+package org.simantics.utils.threads.ua;\r
+\r
+import java.util.concurrent.Callable;\r
+import java.util.concurrent.CancellationException;\r
+import java.util.concurrent.ExecutionException;\r
+import java.util.concurrent.RunnableFuture;\r
+import java.util.concurrent.TimeUnit;\r
+import java.util.concurrent.TimeoutException;\r
+\r
+/**\r
+ * Add stateful monitoring features to runnable and callable.\r
+ * <p>\r
+ * Executing two work instances in parallel causes RuntimeException. \r
+ * \r
+ * @author Toni Kalajainen (toni.kalajainen@vtt.fi)\r
+ */\r
+public class Work<T> extends AbstractState<WorkState, RuntimeException> implements WorkMonitor, RunnableFuture<T> {\r
+ \r
+ public static Work<Object> createMonitor(Runnable r)\r
+ {\r
+ return new Work<Object>(r);\r
+ }\r
+\r
+ public static Work<Object> createMonitor(Runnable r, StateListener<WorkState> listener)\r
+ {\r
+ Work<Object> result = new Work<Object>(r);\r
+ result.addStateListener(listener);\r
+ return result;\r
+ }\r
+ \r
+ public static <T> Work<T> createMonitor(Callable<T> r)\r
+ {\r
+ return new Work<T>(r);\r
+ }\r
+\r
+ public static <T> Work<T> createMonitor(Callable<T> r, StateListener<WorkState> listener)\r
+ {\r
+ Work<T> result = new Work<T>(r);\r
+ result.addStateListener(listener);\r
+ return result;\r
+ }\r
+ \r
+ \r
+ Callable<T> c; \r
+ Runnable r;\r
+ Thread thread;\r
+ transient Exception error;\r
+ transient T result;\r
+ boolean canceled;\r
+ \r
+ public Work(Runnable runnable) {\r
+ super(WorkState.Ready);\r
+ if (runnable == null)\r
+ throw new IllegalArgumentException("null arg");\r
+ \r
+ this.r = runnable;\r
+ }\r
+ \r
+ public Work(Runnable runnable, T result) {\r
+ super(WorkState.Ready);\r
+ if (runnable == null)\r
+ throw new IllegalArgumentException("null arg");\r
+ \r
+ this.r = runnable;\r
+ this.result = result;\r
+ }\r
+ \r
+ public Work(Callable<T> c) {\r
+ super(WorkState.Ready);\r
+ if (c == null)\r
+ throw new IllegalArgumentException("null arg");\r
+ \r
+ this.c = c;\r
+ }\r
+\r
+ @Override\r
+ public void run() {\r
+ WorkState s = getState();\r
+ if (s!=WorkState.Ready) \r
+ throw new RuntimeException("Work must be restarted before it can be reused");\r
+ thread = Thread.currentThread();\r
+ if (setState(WorkState.Working, null, WorkState.READY_STATE)==WorkState.Working) return;\r
+ try { \r
+ if (r!=null)\r
+ r.run();\r
+ else \r
+ result = c.call();\r
+ } catch (Exception e) {\r
+ error = e;\r
+ setState(WorkState.Error);\r
+ }\r
+ WorkState newState = WorkState.Complete;\r
+ synchronized(this) {\r
+ s = getState();\r
+ if (s==WorkState.Interrupting) {\r
+ Thread.interrupted();\r
+ newState = WorkState.Interrupted;\r
+ }\r
+ }\r
+ setState(newState);\r
+ }\r
+\r
+ @Override\r
+ public boolean cancel(boolean mayInterruptIfRunning) {\r
+ synchronized(this) {\r
+ WorkState s = getState();\r
+ if (s != WorkState.Ready && s != WorkState.Working) return false;\r
+ }\r
+ // Attempt cancel\r
+ if (attemptSetState(WorkState.READY_STATE, WorkState.Canceled)==WorkState.Ready) {\r
+ canceled |= true;\r
+ return true;\r
+ }\r
+ // Attempt interrupt\r
+ if (mayInterruptIfRunning && \r
+ attemptSetState(WorkState.WORKING_STATE, WorkState.Interrupting)==WorkState.Working)\r
+ {\r
+ canceled |= true;\r
+ thread.interrupt();\r
+ return true;\r
+ }\r
+ return false;\r
+ }\r
+ \r
+ @Override\r
+ protected boolean isStateTransitionAllowed(WorkState oldState, WorkState newState) {\r
+ return true;\r
+ }\r
+\r
+ // Raise visibility\r
+ @Override\r
+ public void setError(RuntimeException error)\r
+ {\r
+ super.setError(error);\r
+ }\r
+\r
+ /**\r
+ * Reset work for reuse. \r
+ */\r
+ public synchronized void restart() \r
+ {\r
+ WorkState s = getState();\r
+ if (s==WorkState.Ready) return;\r
+ if (!s.isFinalState())\r
+ throw new RuntimeException("Work cannot be restarted until the previous run has completed.");\r
+ setState(WorkState.Ready);\r
+ }\r
+\r
+ @Override\r
+ public Runnable getRunnable() {\r
+ return r;\r
+ }\r
+\r
+ @Override\r
+ public T get() throws InterruptedException, ExecutionException {\r
+ WorkState s = waitForState(WorkState.FINAL_STATES);\r
+ if (s==WorkState.Canceled)\r
+ throw new CancellationException();\r
+ if (s==WorkState.Interrupted)\r
+ throw new InterruptedException();\r
+ if (s==WorkState.Error)\r
+ throw new ExecutionException(error); \r
+ return result;\r
+ }\r
+\r
+ @Override\r
+ public T get(long timeout, TimeUnit unit) throws InterruptedException,\r
+ ExecutionException, TimeoutException {\r
+ WorkState s = waitForState(WorkState.FINAL_STATES, timeout, unit);\r
+ if (s==WorkState.Canceled)\r
+ throw new CancellationException();\r
+ if (s==WorkState.Interrupted)\r
+ throw new InterruptedException();\r
+ if (s==WorkState.Error)\r
+ throw new ExecutionException(error); \r
+ return result;\r
+ }\r
+\r
+ @Override\r
+ public boolean isCancelled() {\r
+ return canceled;\r
+ }\r
+\r
+ @Override\r
+ public boolean isDone() {\r
+ return WorkState.FINAL_STATES.contains(getState());\r
+ }\r
+ \r
+}\r
Code Review / simantics / platform.git / blobdiff