| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.tuscany.sca.core.work.impl; |
| |
| import java.util.Collection; |
| import java.util.Map; |
| import java.util.UUID; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.RejectedExecutionException; |
| import java.util.concurrent.ThreadFactory; |
| |
| import org.apache.tuscany.sca.work.WorkSchedulerException; |
| |
| /** |
| * A thread-pool based implementation for the JSR-237 work manager. |
| * <p/> |
| * <p/> |
| * This implementation supports only local work. |
| * <p/> |
| * TODO Elaborate the implementation. </p> |
| * |
| * @version $Rev$ $Date$ |
| */ |
| public class ThreadPoolWorkManager { |
| |
| // Map of work items currently handled by the work manager |
| private Map<WorkItem, WorkListener> workItems = new ConcurrentHashMap<WorkItem, WorkListener>(); |
| |
| // Thread-pool |
| private ExecutorService executor; |
| |
| /** |
| * Initializes the thread-pool. |
| * |
| * @param threadPoolSize Thread-pool size. If the size <1, then a cached pool is created |
| */ |
| public ThreadPoolWorkManager(int threadPoolSize) { |
| ThreadFactory factory = new ThreadFactory() { |
| public Thread newThread(Runnable r) { |
| Thread thread = new Thread(r); |
| thread.setDaemon(true); |
| return thread; |
| } |
| }; |
| if (threadPoolSize <= 0) { |
| |
| // Creates a new Executor, use a custom ThreadFactory that |
| // creates daemon threads. |
| executor = Executors.newCachedThreadPool(factory); |
| } else { |
| executor = Executors.newFixedThreadPool(threadPoolSize, factory); |
| } |
| } |
| |
| /** |
| * Schedules a unit of work asynchronously. |
| * |
| * @param work Work that needs to be scheduled. |
| * @return Work Work item representing the asynchronous work |
| */ |
| public WorkItem schedule(Work work) throws IllegalArgumentException { |
| return schedule(work, null); |
| } |
| |
| /** |
| * Schedules a unit of work asynchronously. |
| * |
| * @param work Work that needs to be scheduled. |
| * @param workListener Work listener for callbacks. |
| * @return Work Work item representing the asynchronous work |
| */ |
| public WorkItem schedule(Work work, WorkListener workListener) throws IllegalArgumentException { |
| |
| WorkItem workItem = new WorkItem(UUID.randomUUID().toString(), work); |
| if (workListener != null) { |
| workItems.put(workItem, workListener); |
| } |
| workAccepted(workItem, work); |
| if (scheduleWork(work, workItem)) { |
| return workItem; |
| } else { |
| workItem.setStatus(WorkEvent.WORK_REJECTED); |
| if (workListener != null) { |
| workListener.workRejected(new WorkEvent(workItem)); |
| } |
| throw new IllegalArgumentException("Unable to schedule work"); |
| } |
| } |
| |
| /** |
| * Wait for all the specified units of work to finish. |
| * |
| * @param works Units of the work that need to finish. |
| * @param timeout Timeout for waiting for the units of work to finish. |
| */ |
| public boolean waitForAll(Collection works, long timeout) { |
| throw new UnsupportedOperationException("waitForAll not supported"); |
| } |
| |
| /** |
| * Wait for any of the specified units of work to finish. |
| * |
| * @param works Units of the work that need to finish. |
| * @param timeout Timeout for waiting for the units of work to finish. |
| */ |
| public Collection waitForAny(Collection works, long timeout) { |
| throw new UnsupportedOperationException("waitForAny not supported"); |
| } |
| |
| /** |
| * Method provided for subclasses to indicate a work acceptance. |
| * |
| * @param workItem Work item representing the work that was accepted. |
| * @param work Work that was accepted. |
| */ |
| private void workAccepted(final WorkItem workItem, final Work work) { |
| WorkListener listener = workItems.get(workItem); |
| if (listener != null) { |
| workItem.setStatus(WorkEvent.WORK_ACCEPTED); |
| WorkEvent event = new WorkEvent(workItem); |
| listener.workAccepted(event); |
| } |
| } |
| |
| /* |
| * Method to indicate a work start. |
| */ |
| private void workStarted(final WorkItem workItem, final Work work) { |
| WorkListener listener = workItems.get(workItem); |
| if (listener != null) { |
| workItem.setStatus(WorkEvent.WORK_STARTED); |
| WorkEvent event = new WorkEvent(workItem); |
| listener.workStarted(event); |
| } |
| } |
| |
| /* |
| * Method to indicate a work completion. |
| */ |
| private void workCompleted(final WorkItem workItem, final Work work) { |
| workCompleted(workItem, work, null); |
| } |
| |
| /* |
| * Method to indicate a work completion. |
| */ |
| private void workCompleted(final WorkItem workItem, final Work work, final WorkSchedulerException exception) { |
| WorkListener listener = workItems.get(workItem); |
| if (listener != null) { |
| workItem.setStatus(WorkEvent.WORK_COMPLETED); |
| workItem.setResult(work); |
| workItem.setException(exception); |
| WorkEvent event = new WorkEvent(workItem); |
| listener.workCompleted(event); |
| workItems.remove(workItem); |
| } |
| } |
| |
| /* |
| * Schedules the work using the ThreadPool. |
| */ |
| private boolean scheduleWork(final Work work, final WorkItem workItem) { |
| try { |
| executor.execute(new DecoratingWork(workItem, work)); |
| return true; |
| } catch (RejectedExecutionException ex) { |
| return false; |
| } |
| } |
| |
| /* |
| * Class that decorates the original worker so that it can get callbacks when work is done. |
| */ |
| private final class DecoratingWork implements Runnable { |
| |
| // Work item for this work. |
| private WorkItem workItem; |
| |
| // The original work. |
| private Work decoratedWork; |
| |
| /* |
| * Initializes the work item and underlying work. |
| */ |
| private DecoratingWork(final WorkItem workItem, final Work decoratedWork) { |
| this.workItem = workItem; |
| this.decoratedWork = decoratedWork; |
| } |
| |
| /* |
| * Overrides the run method. |
| */ |
| public void run() { |
| workStarted(workItem, decoratedWork); |
| try { |
| decoratedWork.run(); |
| workCompleted(workItem, decoratedWork); |
| } catch (Throwable th) { |
| workCompleted(workItem, decoratedWork, new WorkSchedulerException(th.getMessage(), th)); |
| } |
| } |
| |
| } |
| |
| public void destroy() { |
| executor.shutdown(); |
| } |
| |
| } |
| |