java - executor.shutDownNow() 不会停止执行内部方法

Question

我创建了一个 future 任务并将其提交给 Executor。在 run() 方法中，我创建了一个 placementPlanner 对象。此类中的方法调用其他类。但是，当我调用 executor.shutDownNow() 时，调用的内部方法不会停止执行。如何调用我杀死所有子线程并停止调用方法。代码如下。

static List<Result> invokePlacementPlannerWithTimeout(int timeoutSecs,
        final String requestType, final RequestMap requestMap,
        final ReleaseMap releaseMap, final SysConfig systemConfig,
        final Request request, final SigmaBlade hostData,
        final ServiceLevelData serviceLevelData,
        final List<Service> serviceList, final String transactionID) throws IOException {

    /**
     * Object of ExecutorService interface used for timed execution of Placement
     * Planner.
     */
    ExecutorService executor = Executors.newFixedThreadPool(1);
    /**
     * Creating a final List of Result type.
     */
    final List<Result> resultList = new ArrayList<Result>();
    /**
     * set the executor thread working
     */
    Future<?> future = executor.submit(new Runnable() {

        public void run() {

            try {
                Result result = new Result();
                PlacementPlanner planner = new PlacementPlanner();

                result.setRequestMapACK(planner.getRequestResult(
                            requestMap, systemConfig, request, hostData,
                            serviceLevelData, transactionID,
                            configFileLocation));

                resultList.add(result);
            } catch (Exception e) {
                System.out.println("Exception in run method in invokePlacementPlannerWithTimeout method in Controller");
                throw new RuntimeException(e);
            }
        }

    });

    try {
        /**
         * invoking the future task with specified timeout.
         */
        //  System.out.println(timeoutSecs);
        future.get(timeoutSecs, TimeUnit.MILLISECONDS);

        /**
         * Shutting down the service after successful execution.
         */
        executor.shutdownNow();
    } catch (Exception e) {
        /**
         * Shutting down the service if timeout is occured.
         */
        executor.shutdownNow();

        /**
         * Canceling the task for future use.
         */
        future.cancel(true);

        System.out.println("Timeout Occureed.");
        Runtime.getRuntime().exec("taskkill /F /IM " + "QNSim.exe*");
    }
    return resultList;
}

Answer 1

根据 javadoc

There are no guarantees beyond best-effort attempts to stop processing actively executing tasks. For example, typical implementations will cancel via Thread.interrupt(), so any task that fails to respond to interrupts may never terminate

因此，shutdownNow() 不保证任务立即终止。