SpringBoot定時任務多線程實現示例
測試Spring Boot定時任務沖突時，使用的線程數量
引入依賴：
Spring Boot 2.6.1
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
簡單的測試類
import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
/**
* @author Song Jiangtao
* @date 2021/12/22
* @description:
*/
@Component
@Slf4j
public class Task {
@Scheduled(cron="*/2 * * * * ?")
public void process(){
log.info("do something");
}
@Scheduled(fixedRate = 2000)
public void currentTime(){
log.info("做點什麼");
}
}
啟動類開啟定時任務：@EnableScheduling
測試結果如下：
由結果可見，main線程啟動以後和scheduling-1線程跑瞭兩個任務
由此可見，Spring Boot 定時器 默認是 單線程
我們新增兩個定時任務來看看這樣會有什麼後果
@Scheduled(cron="*/2 * * * * ?")
public void process2() throws InterruptedException {
Thread.sleep(5000L);
log.info("do something use long time");
}
@Scheduled(cron="*/2 * * * * ?")
public void process3() throws InterruptedException {
Thread.sleep(10000L);
log.info("do something use long long time");
}
2021-12-22 16:30:28.735 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication : Starting SpringBootScheduledApplication using Java 1.8.0_202 on TCZ-D with PID 14520 (D:\code\SpringBootScheduled\target\classes started by Administrator in D:\code\SpringBootScheduled) 2021-12-22 16:30:28.738 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication : No active profile set, falling back to default profiles: default 2021-12-22 16:30:29.315 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:29.318 INFO 14520 --- [ main] c.e.s.SpringBootScheduledApplication : Started SpringBootScheduledApplication in 0.937 seconds (JVM running for 3.068) 2021-12-22 16:30:30.002 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:30:40.003 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long long time 2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long time 2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:45.005 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:45.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something use long long time 2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:55.006 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:30:55.007 INFO 14520 --- [ scheduling-1] c.e.springbootscheduled.scheduled.Task : do something
很明顯任務會發生錯亂，嚴重時會導致線程阻塞，最後崩潰
解決方法：引入線程池
新增配置類，配置線程池
package com.example.springbootscheduled.config;
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.ThreadPoolExecutor;
/**
* @author Song Jiangtao
* @date 2021/12/22
* @description:
*/
@Configuration
@EnableAsync
public class TaskConfig {
/**
* 默認線程數
*/
private static final int corePoolSize = 10;
/**
* 最大線程數
*/
private static final int maxPoolSize = 100;
/**
* 允許線程空閑時間（單位：默認為秒）,十秒後就把線程關閉
*/
private static final int keepAliveTime = 10;
/**
* 緩沖隊列數
*/
private static final int queueCapacity = 200;
/**
* 線程池名前綴
*/
private static final String threadNamePrefix = "task-thread-";
/**
* bean的名稱，默認為 首字小寫 方法名
*/
@Bean("taskExecutor")
public ThreadPoolTaskExecutor getThread() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(corePoolSize);
executor.setMaxPoolSize(maxPoolSize);
executor.setQueueCapacity(keepAliveTime);
executor.setKeepAliveSeconds(queueCapacity);
executor.setThreadNamePrefix(threadNamePrefix);
//線程池拒絕策略
executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
executor.initialize();
return executor;
}
}
每個定時任務添加註解 @Async("taskExecutor")
@Async("taskExecutor")
@Scheduled(fixedRate = 2000)
public void currentTime(){
log.info("做點什麼");
}
啟動測試
2021-12-22 16:41:36.141 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : Starting SpringBootScheduledApplication using Java 1.8.0_202 on TCZ-D with PID 19424 (D:\code\SpringBootScheduled\target\classes started by Administrator in D:\code\SpringBootScheduled) 2021-12-22 16:41:36.143 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : No active profile set, falling back to default profiles: default 2021-12-22 16:41:36.991 INFO 19424 --- [ main] c.e.s.SpringBootScheduledApplication : Started SpringBootScheduledApplication in 1.325 seconds (JVM running for 3.392) 2021-12-22 16:41:37.008 INFO 19424 --- [ task-thread-1] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:38.001 INFO 19424 --- [ task-thread-2] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:41:38.991 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:40.003 INFO 19424 --- [ task-thread-8] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:41:40.991 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:42.001 INFO 19424 --- [ task-thread-10] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:41:42.989 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:43.002 INFO 19424 --- [ task-thread-3] c.e.springbootscheduled.scheduled.Task : do something use long time 2021-12-22 16:41:44.002 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:41:44.990 INFO 19424 --- [ task-thread-5] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:45.002 INFO 19424 --- [ task-thread-6] c.e.springbootscheduled.scheduled.Task : do something use long time 2021-12-22 16:41:46.001 INFO 19424 --- [ task-thread-9] c.e.springbootscheduled.scheduled.Task : do something 2021-12-22 16:41:46.990 INFO 19424 --- [ task-thread-6] c.e.springbootscheduled.scheduled.Task : 做點什麼 2021-12-22 16:41:47.002 INFO 19424 --- [ task-thread-1] c.e.springbootscheduled.scheduled.Task : do something use long time 2021-12-22 16:41:48.002 INFO 19424 --- [ task-thread-4] c.e.springbootscheduled.scheduled.Task : do something use long long time
到此這篇關於SpringBoot定時任務多線程實現示例的文章就介紹到這瞭,更多相關SpringBoot定時任務多線程內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！
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