// 啟動類
@EnableAsync
@EnableWebSecurity
@ServletComponentScan
@SpringBootApplication(scanBasePackages={"com.example.demo"})
public class DemoApplication {
	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}
}

// 線程池配置類
@Slf4j
@Configuration
public class BootThreadpoolConfig {
    // 配置核心線程數(shù)
    private int corePoolSize = 5;
    // 配置最大線程數(shù)
    private int maxPoolSize = 20;
    // 配置任務隊列的長度
    private int queueCapacity = 500;
    // 配置任務的空閑時間
    private int aliveSeconds = 600;
    // 配置線程前綴
    private String namePrefix = "localThreadPool";
    // 自定義線程池, 起個好記的名
    @Bean(name = "localBootAsyncExecutor")
    public Executor asyncServiceExecutor() {
        log.info("初始化 springboot 線程池");
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        //配置核心線程數(shù)
        executor.setCorePoolSize(corePoolSize);
        //配置最大線程數(shù)
        executor.setMaxPoolSize(maxPoolSize);
        //配置隊列大小
        executor.setQueueCapacity(queueCapacity);
        //配置線程池中的線程的名稱前綴
        executor.setThreadNamePrefix(namePrefix);
        //配置線程的空閑時間
        executor.setKeepAliveSeconds(aliveSeconds);
        // RejectedExecutionHandler：當pool已經(jīng)達到max size的時候，如何處理新任務
        // CallerRunsPolicy：不在新線程中執(zhí)行任務，而是有調用者所在的線程來執(zhí)行
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        //執(zhí)行初始化
        executor.initialize();
        log.info("springboot 線程池初始化完畢");
        return executor;
    }
}

// 異步執(zhí)行代碼
@Service("asyncExecutorTest")
public class AsyncExecutorTest {
    // 異步執(zhí)行的方法, 注解內為自定義線程池類名
    @Async("localBootAsyncExecutor")
    public Future<Integer> test1(Integer i) throws InterruptedException {
        Thread.sleep(100);
        System.out.println("@Async 執(zhí)行: " + i);
        return new AsyncResult(i);
    }
    // 這里使用其它方式調用，詳見后面的 service3 方法
    public Integer test2(Integer i) throws InterruptedException {
        Thread.sleep(100);
        System.out.println(" excute.run 執(zhí)行: " + i);
        return i;
    }
}

// 業(yè)務 service
@Service("asyncExcutorService")
public class AsyncExcutorService {
    @Autowired
    AsyncExecutorTest asyncExecutorTest;
    @Autowired
    Executor localBootAsyncExecutor;
    // 測試 無返回值異步執(zhí)行
    public void service1(){
        System.out.println("service1 執(zhí)行----->");
        for (int i = 0; i < 50; i++) {
            try {
                asyncExecutorTest.test1(i);
            } catch (InterruptedException e) {
                System.out.println("service1執(zhí)行出錯");
            }
        }
        System.out.println("service1 結束----->");
    }
    // 測試 有返回值異步執(zhí)行
    public void service2(){
        long l = System.currentTimeMillis();
        System.out.println("service2 執(zhí)行----->");
        List<Future> result = new ArrayList<>();
        try {
            for (int i = 0; i < 300; i++) {
                Future<Integer> integerFuture = asyncExecutorTest.test1(i);
                result.add(integerFuture);
            }
            for (Future future : result) {
                System.out.println(future.get());
            }
        } catch (InterruptedException | ExecutionException e) {
            System.out.println("service2執(zhí)行出錯");
        }
        System.out.println("service2 結束----->" + (System.currentTimeMillis() - l));
    }
    // 測試 有返回值異步執(zhí)行
    public void service3(){
        long l = System.currentTimeMillis();
        List<Integer> result = new ArrayList<>();
        try {
            System.out.println("service3 執(zhí)行----->");
            int total = 300;
            CountDownLatch latch = new CountDownLatch(total);
            for (int i = 0; i < total; i++) {
                final int y = i;
                localBootAsyncExecutor.execute(() -> {
                    try {
                        result.add(asyncExecutorTest.test2(y));
                    } catch (InterruptedException e) {
                        System.out.println("service3執(zhí)行出錯");
                    } finally {
                        latch.countDown();
                    }
                });
            }
            latch.await();
        } catch (InterruptedException e) {
            System.out.println("service3執(zhí)行出錯");
        }
        System.out.println("service3 結束----->" + (System.currentTimeMillis() - l));
    }
}