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1.自定義線程池

@EnableAsync
@Configuration
public class BeanConfig {
    @Bean("taskExecutor")
    public Executor initTaskExecutor(){
        ThreadPoolTaskExecutor executor= new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(5);
        executor.setMaxPoolSize(20);
        executor.setQueueCapacity(200);
        executor.setThreadNamePrefix("taskExecutor-");
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        return executor;
    }
}

上面我們通過使用 ThreadPoolTaskExecutor創(chuàng)建了一個(gè)線程池，同時(shí)設(shè)置了以下這些參數(shù)：
?核心線程數(shù)10：線程池創(chuàng)建時(shí)候初始化的線程數(shù)
?最大線程數(shù)20：線程池最大的線程數(shù)，只有在緩沖隊(duì)列滿了之后才會(huì)申請(qǐng)超過核心線程數(shù)的線程
?緩沖隊(duì)列200：用來緩沖執(zhí)行任務(wù)的隊(duì)列
?允許線程的空閑時(shí)間60秒：當(dāng)超過了核心線程出之外的線程在空閑時(shí)間到達(dá)之后會(huì)被銷毀
?線程池名的前綴：設(shè)置好了之后可以方便我們定位處理任務(wù)所在的線程池
?線程池對(duì)拒絕任務(wù)的處理策略：這里采用了 CallerRunsPolicy策略，當(dāng)線程池沒有處理能力的時(shí)候，該策略會(huì)直接在 execute 方法的調(diào)用線程中運(yùn)行被拒絕的任務(wù)；如果執(zhí)行程序已關(guān)閉，則會(huì)丟棄該任務(wù)

2.定義任務(wù)執(zhí)行類ExecutorTaskService

@Service
public class ExecutorTaskService {

    @Async("taskExecutor")
    public void doTask1() throws InterruptedException {
        System.out.println("開始做任務(wù)一");
        long start = System.currentTimeMillis();
        Thread.sleep(2000);
        long end = System.currentTimeMillis();
        System.out.println("完成任務(wù)一，耗時(shí)：" + (end - start) + "毫秒");
    }

    @Async("taskExecutor")
    public void doTask2() throws InterruptedException {
        System.out.println("開始做任務(wù)二");
        long start = System.currentTimeMillis();
        Thread.sleep(1000);
        long end = System.currentTimeMillis();
        System.out.println("完成任務(wù)二，耗時(shí)：" + (end - start) + "毫秒");
    }

    @Async("taskExecutor")
    public void doTask3() throws InterruptedException {
        System.out.println("開始做任務(wù)三");
        long start = System.currentTimeMillis();
        Thread.sleep(500);
        long end = System.currentTimeMillis();
        System.out.println("完成任務(wù)三，耗時(shí)：" + (end - start) + "毫秒");
    }
}

3.定義controller

@RequestMapping("/executor")
@Controller
public class ExecutorTaskCtrl {

    @Autowired
    private ExecutorTaskService executorTaskService;

    @RequestMapping(value = "/doTask",method = RequestMethod.GET)
    @ResponseBody
    public void doTask() throws InterruptedException {
        executorTaskService.doTask1();
        executorTaskService.doTask2();
        executorTaskService.doTask3();
    }
}

訪問http://localhost:9999/executor/doTask 查看打印結(jié)果：
開始做任務(wù)二
開始做任務(wù)一
開始做任務(wù)三
完成任務(wù)三，耗時(shí)：501毫秒
完成任務(wù)二，耗時(shí)：1001毫秒
完成任務(wù)一，耗時(shí)：2001毫秒

參考原創(chuàng)： 翟永超