springboot 異步調用

異步調用

啓動類：添加@EnableAsync註解

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

service方法上添加@Async註解

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");
    }

}

異步線程池

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;
 
/**
 * 線程池配置
 * @author zhh
 *
 */
@Configuration
@EnableAsync
public class ThreadPoolTaskConfig {
	
	private static final int corePoolSize = 10;       		// 核心線程數（默認線程數）
	private static final int maxPoolSize = 100;			    // 最大線程數
	private static final int keepAliveTime = 10;			// 容許線程空閒時間（單位：默認爲秒）
	private static final int queueCapacity = 200;			// 緩衝隊列數
	private static final String threadNamePrefix = "Async-Service-"; // 線程池名前綴
	
	@Bean("taskExecutor") // bean的名稱，默認爲首字母小寫的方法名
	public ThreadPoolTaskExecutor taskExecutor(){
		ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
		executor.setCorePoolSize(corePoolSize);   
		executor.setMaxPoolSize(maxPoolSize);
		executor.setQueueCapacity(queueCapacity);
		executor.setKeepAliveSeconds(keepAliveTime);
		executor.setThreadNamePrefix(threadNamePrefix);
		
		// 線程池對拒絕任務的處理策略
		executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
		// 初始化
		executor.initialize();
		return executor;
	}
}

 測試

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);
 
	// 發送提醒短信 1
	@Async("taskExecutor")
	public void sendMessage1() throws InterruptedException {
		log.info("發送短信方法---- 1   執行開始");
		Thread.sleep(5000); // 模擬耗時
		log.info("發送短信方法---- 1   執行結束");
	}
	
	// 發送提醒短信 2
	@Async("taskExecutor")
	public void sendMessage2() throws InterruptedException {
		
		log.info("發送短信方法---- 2   執行開始");
		Thread.sleep(2000); // 模擬耗時
		log.info("發送短信方法---- 2   執行結束");
	}
}

注意事項：

以下方式會使@Async失效
1、異步方法使用static修飾
2、異步類沒有使用@Component註解（或其餘註解）致使spring沒法掃描到異步類
3、異步方法不能與異步方法在同一個類中
4、類中須要使用@Autowired或@Resource等註解自動注入，不能本身手動new對象
5、若是使用SpringBoot框架必須在啓動類中增長@EnableAsync註解
6、在Async 方法上標註@Transactional是沒用的。 在Async 方法調用的方法上標註@Transactional 有效。