springboot @Async 注解如何实现方法异步

package com.xxx.xxx.xxx;
import java.util.concurrent.ThreadPoolExecutor;
import org.springframework.boot.web.support.SpringBootServletInitializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.task.TaskExecutor;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
/**
 * 类功能说明:服务生产者启动类
 * <p>
 * <strong></strong>
 * </p>
 *
 * @version
 * @author
 * @since 1.8
 */
@Configuration
@EnableAsync
public class Application extends SpringBootServletInitializer { 
    @Bean
    public TaskExecutor taskExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        // 设置核心线程数
        executor.setCorePoolSize(5);
        // 设置最大线程数
        executor.setMaxPoolSize(60);
        // 设置队列容量
        executor.setQueueCapacity(20);
        // 设置线程活跃时间（秒）
        executor.setKeepAliveSeconds(60);
        // 设置默认线程名称
        executor.setThreadNamePrefix("what-");
        // 设置拒绝策略
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        // 等待所有任务结束后再关闭线程池
        executor.setWaitForTasksToCompleteOnShutdown(true);        
        return executor;
    }    
}

package com.xxx.xxx.service.impl; 
import java.util.concurrent.Future; 
import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.AsyncResult;
import org.springframework.stereotype.Service; 
import com.xxx.xxx.service.XXXAsyncService ;
 
@Service
public class XXXAsyncServiceImpl implements XXXAsyncService { 
    @Async
    public Future<Long> rtn1() throws Exception {
        //do something
        //有返回值的时候，可以返回string，long之类的。
        return new AsyncResult<>(1);
    } 
    @Async
    public void rtn2() throws Exception {
        //do something
        //这个可以没有返回值.
    }
}

package com.xxx.xxx.controller; 
import java.util.concurrent.Future; 
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController; 
import com.xxx.xxx.service.XXXAsyncService;
 
@RestController
@RequestMapping(value="/xxx") 
public class XXXAsyncController { 
 @Autowired
 private XXXAsyncService xxxAsyncService; 
 /**
  * 这里调用异步方法
  */
    @RequestMapping(value = "/xxx")
 public void dodo() throws Exception {     
  int threads = 10;//十个线程
        List<Future<Long>> list = new ArrayList<>();
        for(int i = 0;i < threads; i++){
         //这里循环调用异步方法。
      //如果存在大量数据，可以在这里把数据切片，然后循环调用，分批处理数据。效率杠杠的。
   list .add(xxxAsyncService.rtn1());
        }
        long count = 0;
        for(Future<Long> l : tsfCountList) {
         //异步调用需要返回值的时候，这里可以把返回值都放入到list集合中，然后可以统一处理。 这里的get()是阻塞的，因为需要所以异步方法返回，在继续执行。
         count += l.get();
        }
        System.out.println("调用次数：" + count)；
 }
}

@Configuration
@EnableAsync
public class SpringAsyncConfig { ... }

protected void doExecute(Runnable task) {
    Thread thread = (this.threadFactory != null ? this.threadFactory.newThread(task) : createThread(task));
    thread.start();
}

package com.deppon.ptos.load.config; 
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor; 
import java.util.concurrent.Executor;
import java.util.concurrent.ThreadPoolExecutor;
 
/**
 * @Description: 异步线程管理
 * @Author:   LYH
 * @CreateDate: 2019/6/27 8:54
 * @Version: 1.0
 * @JDK: 1.8
 */
@Configuration
@EnableAsync
@Slf4j
public class ExecutorConfig {  
    @Value("${async.executor.thread.core_pool_size}")
    private int corePoolSize;
    @Value("${async.executor.thread.max_pool_size}")
    private int maxPoolSize;
    @Value("${async.executor.thread.queue_capacity}")
    private int queueCapacity;
    @Value("${async.executor.thread.name.prefix}")
    private String namePrefix;
 
    @Bean(name = "asyncServiceExecutor")
    public Executor asyncServiceExecutor() {
        log.info("start asyncServiceExecutor");
        ThreadPoolTaskExecutor executor = new VisiableThreadPoolTaskExecutor();
        //配置核心线程数
        executor.setCorePoolSize(corePoolSize);
        //配置最大线程数
        executor.setMaxPoolSize(maxPoolSize);
        //配置队列大小
        executor.setQueueCapacity(queueCapacity);
        //配置线程池中的线程的名称前缀
        executor.setThreadNamePrefix(namePrefix);
 
        // rejection-policy：当pool已经达到max size的时候，如何处理新任务
        // CALLER_RUNS：不在新线程中执行任务，而是有调用者所在的线程来执行
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        //执行初始化
        executor.initialize();
        return executor;
    }
}

package com.deppon.ptos.load.config;  
import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.stereotype.Component;
import org.springframework.util.concurrent.ListenableFuture; 
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadPoolExecutor;
 
/**
 * @Description: 打印异步线程的执行情况   使用Callbale Future 来返回线程的信息
 * @Author: 633805  LYH
 * @CreateDate: 2019/6/27 8:59
 * @Version: 1.0
 * @JDK: 1.8
 */
@Component
@Slf4j
public class VisiableThreadPoolTaskExecutor extends ThreadPoolTaskExecutor {  
    private void showThreadPoolInfo(String prefix) {
        ThreadPoolExecutor threadPoolExecutor = getThreadPoolExecutor(); 
        if (null == threadPoolExecutor) {
            return;
        }
 
        log.info("{}, {},taskCount [{}], completedTaskCount [{}], activeCount [{}], queueSize [{}]",
                this.getThreadNamePrefix(),
                prefix,
                threadPoolExecutor.getTaskCount(),
                threadPoolExecutor.getCompletedTaskCount(),
                threadPoolExecutor.getActiveCount(),
                threadPoolExecutor.getQueue().size());
    }
 
    @Override
    public void execute(Runnable task) {
        showThreadPoolInfo("1. do execute");
        super.execute(task);
    }
 
    @Override
    public void execute(Runnable task, long startTimeout) {
        showThreadPoolInfo("2. do execute");
        super.execute(task, startTimeout);
    }
 
    @Override
    public Future<?> submit(Runnable task) {
        showThreadPoolInfo("1. do submit");
        return super.submit(task);
    }
 
    @Override
    public <T> Future<T> submit(Callable<T> task) {
        showThreadPoolInfo("2. do submit");
        return super.submit(task);
    }
 
    @Override
    public ListenableFuture<?> submitListenable(Runnable task) {
        showThreadPoolInfo("1. do submitListenable");
        return super.submitListenable(task);
    }
 
    @Override
    public <T> ListenableFuture<T> submitListenable(Callable<T> task) {
        showThreadPoolInfo("2. do submitListenable");
        return super.submitListenable(task);
    }
}

@Async("asyncServiceExecutor")