快捷導(dǎo)航

AsyncConfigurerSupport自定義異步線程池處理異常

更新時間：2023年06月13日 14:29:43 作者：老鼠AI大米_Java全棧

這篇文章主要為大家介紹了AsyncConfigurerSupport自定義異步線程池處理異常詳解，有需要的朋友可以借鑒參考下，希望能夠有所幫助，祝大家多多進步，早日升職加薪

一、AsyncConfigurerSupport 簡介

spring 中開啟異步只要在配置類加上
@EnableAsync 同時在service方法中加上@Async即可，注意service中的方法想要異步調(diào)用必須是通過注入調(diào)用(spring 代理)。

@Service
public class ServiceA{
   public void testA(){
       testB();
   }
   @Async
   public void testB(){
   }
}

上述方法在調(diào)用testA時是同步調(diào)用，而非異步調(diào)用，方法內(nèi)部的直接調(diào)用是沒有經(jīng)過spring 代理的。

二、自定義異步調(diào)用的線程池和異常處理

AsyncConfigurerSupport 只定義了兩個方法分別用于自定義異步線程池、異步產(chǎn)生的異常捕獲，通過實現(xiàn)此類即可實現(xiàn)自定義的異步線程池。

demo如下:

新建子類 AsyncConfigHandler

@Configuration
@EnableAsync
public class AsyncConfigHandler extends AsyncConfigurerSupport {
    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(5);
        executor.setMaxPoolSize(10);
        executor.setQueueCapacity(10);
        executor.initialize();
        return executor;
    }
    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return new MyAsyncUncaughtExceptionHandler();
    }
    @Bean   // /actuator/shutdown
    @Override
    public Executor getAsyncExecutor2() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setTaskDecorator(new SomeTaskDecorator());
        executor.setCorePoolSize(4);
        executor.setMaxPoolSize(8);
        executor.setQueueCapacity(100);
        executor.setAllowCoreThreadTimeOut(false);
        executor.setKeepAliveSeconds(0);
        executor.setThreadNamePrefix("DefaultAsync-");
        executor.setWaitForTasksToCompleteOnShutdown(true); // ? ????? ??
        executor.initialize();
        return executor;
    }
    static class SomeTaskDecorator implements TaskDecorator {
        @Override
        public Runnable decorate(Runnable runnable) {
            return () -> {
                try {
                    log.info("Some Task Decorator Start");
                    runnable.run();
                } finally {
                    log.info("Some Task Decorator End");
                }
            };
        }
    }
}
class MyAsyncUncaughtExceptionHandler implements AsyncUncaughtExceptionHandler {
    @Override
    public void handleUncaughtException(Throwable ex, Method method, Object... params) {
        System.out.println("class#method: " + method.getDeclaringClass().getName() + "#" + method.getName());
        System.out.println("type        : " + ex.getClass().getName());
        System.out.println("exception   : " + ex.getMessage());
    }
}

編寫支持異步調(diào)用注解@Async的 DemoService

@Service
public class DemoService {
    @Async
    public void testAsync() throws InterruptedException {
        System.out.println("這里是異步方法");
        TimeUnit.SECONDS.sleep(10);
        int i = 1 / 0;
    }
}

編寫測試 controller

@RestController
@RequestMapping(value = "time")
public class DemoController {
    @Autowired
    private DemoService demoService;
    @RequestMapping(value = "getTimeAndAsync")
    public String getTimeAndAsync() throws InterruptedException {
        demoService.testAsync();
        return "異步加載=》" + new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
    }
}

新建spring boot應(yīng)用的步驟省略

訪問 http://localhost:8080/time/getTimeAndAsync

瀏覽器會立即輸出