springboot 线程池配置

package com.example.demo.async;

import lombok.extern.slf4j.Slf4j;
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;

/**
 * @author yg
 * @description TODO
 * @date 2023-06-14 22:31
 */
@Configuration
@EnableAsync
@Slf4j
public class AsyncConfiguration {

    @Bean("doSomethingExecutor")
    public Executor doSomethingExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        // 核心线程数：线程池创建时候初始化的线程数
        executor.setCorePoolSize(10);
        // 最大线程数：线程池最大的线程数，只有在缓冲队列满了之后才会申请超过核心线程数的线程
        executor.setMaxPoolSize(20);
        // 缓冲队列：用来缓冲执行任务的队列
        executor.setQueueCapacity(500);
        // 允许线程的空闲时间60秒：当超过了核心线程之外的线程在空闲时间到达之后会被销毁
        executor.setKeepAliveSeconds(60);
        // 线程池名的前缀：设置好了之后可以方便我们定位处理任务所在的线程池
        executor.setThreadNamePrefix("do-something-");
        // 缓冲队列满了之后的拒绝策略：由调用线程处理（一般是主线程）
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.DiscardPolicy());
        executor.initialize();
        log.info("doSomethingExecutor 初始化完毕，executor.getCorePoolSize() = {}", executor.getCorePoolSize());
        return executor;
    }

}

线程方法使用：

1，开启异步

注解开启 @EnableAsync

2，异步线程使用

方法添加 @Async("doSomethingExecutor")

  @Async("doSomethingExecutor")
    public CompletableFuture doSomething1(String message) throws InterruptedException {
        log.info("do something1: {}", message);
        Thread.sleep(1000);
        return CompletableFuture.completedFuture("do something1: " + message);
        //return AsyncResult.forValue("do something11: " + message);
    }

    @Async("doSomethingExecutor")
    public CompletableFuture doSomething2(String message) throws InterruptedException {
        log.info("do something2: {}", message);
        Thread.sleep(1000);
        return CompletableFuture.completedFuture("; do something2: " + message);
    }

    @Async("doSomethingExecutor")
    public CompletableFuture doSomething3(String message) throws InterruptedException {
        log.info("do something3: {}", message);
        Thread.sleep(1000);
        return CompletableFuture.completedFuture("; do something3: " + message);
    }

3，调用方法

@SneakyThrows
    @ApiOperation("异步 有返回值")
    @GetMapping("/open/somethings")
    public String somethings() {
        CompletableFuture createOrder = asyncService.doSomething1("create order");
        CompletableFuture reduceAccount = asyncService.doSomething2("reduce account");
        CompletableFuture saveLog = asyncService.doSomething3("save log");

        // 等待所有任务都执行完
        CompletableFuture.allOf(createOrder, reduceAccount, saveLog).join();

        // 获取每个任务的返回结果
        String result = createOrder.get() + reduceAccount.get() + saveLog.get();
        return result;
    }

返回结果：

do something1: create order; do something2: reduce account; do something3: save log

打印结果

2023-06-15 23:36:43.609  INFO 16016 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
2023-06-15 23:36:43.609  INFO 16016 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
2023-06-15 23:36:43.611  INFO 16016 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 2 ms
2023-06-15 23:36:43.635  INFO 16016 --- [nio-8080-exec-1] com.example.demo.async.AsyncService      : do something1: create order
2023-06-15 23:36:44.655  INFO 16016 --- [nio-8080-exec-1] com.example.demo.async.AsyncService      : do something2: reduce account
2023-06-15 23:36:45.669  INFO 16016 --- [nio-8080-exec-1] com.example.demo.async.AsyncService      : do something3: save log