springboot 异步调用

异步调用

启动类：添加@EnableAsync注解

@SpringBootApplication
@EnableAsync
public class Application{

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

service方法上添加@Async注解

import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;

@Service
public class UserService {

    @Async
    public void sendSms(){
        System.out.println("####sendSms####   2");
        IntStream.range(0, 5).forEach(d -> {
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        });
        System.out.println("####sendSms####   3");
    }

}

异步线程池

配置

package com.boot.common.conf;

import java.util.concurrent.ThreadPoolExecutor;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

/**
 * 线程池配置
 * @author zhh
 *
 */
@Configuration
@EnableAsync
public class ThreadPoolTaskConfig {

	private static final int corePoolSize = 10;       		// 核心线程数（默认线程数）
	private static final int maxPoolSize = 100;			    // 最大线程数
	private static final int keepAliveTime = 10;			// 允许线程空闲时间（单位：默认为秒）
	private static final int queueCapacity = 200;			// 缓冲队列数
	private static final String threadNamePrefix = "Async-Service-"; // 线程池名前缀

	@Bean("taskExecutor") // bean的名称，默认为首字母小写的方法名
	public ThreadPoolTaskExecutor taskExecutor(){
		ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
		executor.setCorePoolSize(corePoolSize);
		executor.setMaxPoolSize(maxPoolSize);
		executor.setQueueCapacity(queueCapacity);
		executor.setKeepAliveSeconds(keepAliveTime);
		executor.setThreadNamePrefix(threadNamePrefix);

		// 线程池对拒绝任务的处理策略
		executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
		// 初始化
		executor.initialize();
		return executor;
	}
}

 测试

package com.boot.test1.service;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;

@Service
public class TranTest2Service {
	Logger log = LoggerFactory.getLogger(TranTest2Service.class);

	// 发送提醒短信 1
	@Async("taskExecutor")
	public void sendMessage1() throws InterruptedException {
		log.info("发送短信方法---- 1   执行开始");
		Thread.sleep(5000); // 模拟耗时
		log.info("发送短信方法---- 1   执行结束");
	}

	// 发送提醒短信 2
	@Async("taskExecutor")
	public void sendMessage2() throws InterruptedException {

		log.info("发送短信方法---- 2   执行开始");
		Thread.sleep(2000); // 模拟耗时
		log.info("发送短信方法---- 2   执行结束");
	}
}

注意事项：

如下方式会使@Async失效
一、异步方法使用static修饰
二、异步类没有使用@Component注解（或其他注解）导致spring无法扫描到异步类
三、异步方法不能与异步方法在同一个类中
四、类中需要使用@Autowired或@Resource等注解自动注入，不能自己手动new对象
五、如果使用SpringBoot框架必须在启动类中增加@EnableAsync注解
六、在Async 方法上标注@Transactional是没用的。 在Async 方法调用的方法上标注@Transactional 有效。