当同时调用完成activiti任务时，TaskListener对完成任务的运行次数超过一次

Question

当我同时调用完整方法时，PostpareTaskListener.notify执行3次，如何在执行notify方法之前只执行一次，另外2次执行Thorw异常？

public static void main(String args[]){     
    Logger log = LoggerFactory.getLogger("");

    final ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();

    new Thread(new Runnable() {

        @Override
        public void run() {
            processEngine.getTaskService().complete("141209", null);

        }
    }).start();

    new Thread(new Runnable() {

        @Override
        public void run() {
            processEngine.getTaskService().complete("141209", null);

        }
    }).start();

    processEngine.getTaskService().complete("141209", null);
}


public class PostpareTaskListener implements TaskListener{
    @Override
    public void notify(DelegateTask task) {
        // TODO Auto-generated method stub

        task.setVariable("result", "false");

        System.out.println("================post pare ================");

    }
}

Answer 1

也许你可以通过以下方式获得任务状态：

task.isSuspended();

毕竟，如果您尝试完成已完成的任务，我希望activit会抛出异常：

org.activiti.engine.ActivitiObjectNotFoundException: Cannot find task with id 141209

设置变量可能会有所帮助：

Boolean executed = (Boolean) task.getVariable("executed");
if (executed) {
    return;
}
task.setVariable("executed", true);