How can I shutdown Spring task executor/scheduler pools before all other beans in the web app are destroyed?

Question

In a Spring web application I have several DAO and service layer beans. One service layer bean has annotated @Async / @Scheduled methods. These methods depend on other (auto

Answer 1

I have added below code to terminate tasks you can use it. You may change the retry numbers.

package com.xxx.test.schedulers;

import java.util.Map;
import java.util.concurrent.TimeUnit;

import org.apache.log4j.Logger;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextClosedEvent;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.stereotype.Component;

import com.xxx.core.XProvLogger;

@Component
class ContextClosedHandler implements ApplicationListener , ApplicationContextAware,BeanPostProcessor{


private ApplicationContext context;

public Logger logger = XProvLogger.getInstance().x;

public void onApplicationEvent(ContextClosedEvent event) {


    Map schedulers = context.getBeansOfType(ThreadPoolTaskScheduler.class);

    for (ThreadPoolTaskScheduler scheduler : schedulers.values()) {         
        scheduler.getScheduledExecutor().shutdown();
        try {
            scheduler.getScheduledExecutor().awaitTermination(20000, TimeUnit.MILLISECONDS);
            if(scheduler.getScheduledExecutor().isTerminated() || scheduler.getScheduledExecutor().isShutdown())
                logger.info("Scheduler "+scheduler.getThreadNamePrefix() + " has stoped");
            else{
                logger.info("Scheduler "+scheduler.getThreadNamePrefix() + " has not stoped normally and will be shut down immediately");
                scheduler.getScheduledExecutor().shutdownNow();
                logger.info("Scheduler "+scheduler.getThreadNamePrefix() + " has shut down immediately");
            }
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    Map executers = context.getBeansOfType(ThreadPoolTaskExecutor.class);

    for (ThreadPoolTaskExecutor executor: executers.values()) {
        int retryCount = 0;
        while(executor.getActiveCount()>0 && ++retryCount<51){
            try {
                logger.info("Executer "+executor.getThreadNamePrefix()+" is still working with active " + executor.getActiveCount()+" work. Retry count is "+retryCount);
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        if(!(retryCount<51))
            logger.info("Executer "+executor.getThreadNamePrefix()+" is still working.Since Retry count exceeded max value "+retryCount+", will be killed immediately");
        executor.shutdown();
        logger.info("Executer "+executor.getThreadNamePrefix()+" with active " + executor.getActiveCount()+" work has killed");
    }
}


@Override
public void setApplicationContext(ApplicationContext context)
        throws BeansException {
    this.context = context;

}


@Override
public Object postProcessAfterInitialization(Object object, String arg1)
        throws BeansException {
    return object;
}


@Override
public Object postProcessBeforeInitialization(Object object, String arg1)
        throws BeansException {
    if(object instanceof ThreadPoolTaskScheduler)
        ((ThreadPoolTaskScheduler)object).setWaitForTasksToCompleteOnShutdown(true);
    if(object instanceof ThreadPoolTaskExecutor)
        ((ThreadPoolTaskExecutor)object).setWaitForTasksToCompleteOnShutdown(true);
    return object;
}

}