目录
依赖pom.xml
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.7.7</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project>
1、同步任务
应用启动类
package com.example.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
同步任务,耗时2秒
package com.example.demo.service; import lombok.extern.slf4j.Slf4j; import org.springframework.scheduling.annotation.Async; import org.springframework.scheduling.annotation.AsyncResult; import org.springframework.stereotype.Service; import java.util.concurrent.Future; @Service @Slf4j public class TaskService { /** * 同步任务 * @throws InterruptedException */ public void syncTask() throws InterruptedException { Thread.sleep(1000 * 2); System.out.println("syncTask"); } }
控制器
package com.example.demo.controller; import com.example.demo.service.TaskService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.concurrent.CompletableFuture; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; @RestController @RequestMapping("/task") @Slf4j public class TaskController { @Autowired private TaskService taskService; @GetMapping("/syncTask") public String syncTask() throws InterruptedException { long start = System.currentTimeMillis(); taskService.syncTask(); long end = System.currentTimeMillis(); log.info("time: {}", end - start); return "success"; } }
请求接口:等待2秒后返回
GET http://localhost:8080/task/syncTask Accept: application/json
2、@Async 异步任务-无返回值
启动类需要加上注解:@EnableAsync
package com.example.demo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.scheduling.annotation.EnableAsync; @SpringBootApplication @EnableAsync public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
异步任务
package com.example.demo.service; import lombok.extern.slf4j.Slf4j; import org.springframework.scheduling.annotation.Async; import org.springframework.scheduling.annotation.AsyncResult; import org.springframework.stereotype.Service; import java.util.concurrent.Future; @Service @Slf4j public class TaskService { /** * 异步任务 * @throws InterruptedException */ @Async public void asyncTask() throws InterruptedException { Thread.sleep(1000 * 2); System.out.println("asyncTask"); } }
控制器
package com.example.demo.controller; import com.example.demo.service.TaskService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.concurrent.CompletableFuture; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; @RestController @RequestMapping("/task") @Slf4j public class TaskController { @Autowired private TaskService taskService; @GetMapping("/asyncTask") public String asyncTask() throws InterruptedException { long start = System.currentTimeMillis(); taskService.asyncTask(); long end = System.currentTimeMillis(); log.info("time: {}", end - start); return "success"; } }
请求接口:无等待,直接返回
GET http://localhost:8080/task/asyncTask Accept: application/json
3、@Async 异步任务-有返回值
异步任务
package com.example.demo.service; import lombok.extern.slf4j.Slf4j; import org.springframework.scheduling.annotation.Async; import org.springframework.scheduling.annotation.AsyncResult; import org.springframework.stereotype.Service; import java.util.concurrent.Future; @Service @Slf4j public class TaskService { /** * 异步任务, 有返回值 * @throws InterruptedException */ @Async public Future<String> asyncTaskFuture() throws InterruptedException { Thread.sleep(1000 * 2); System.out.println("asyncTaskFuture"); return new AsyncResult<>("asyncTaskFuture"); } }
控制器
package com.example.demo.controller; import com.example.demo.service.TaskService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.concurrent.CompletableFuture; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; @RestController @RequestMapping("/task") @Slf4j public class TaskController { @Autowired private TaskService taskService; @GetMapping("/asyncTaskFuture") public String asyncTaskFuture() throws InterruptedException, ExecutionException { long start = System.currentTimeMillis(); Future<String> future = taskService.asyncTaskFuture(); // 线程等待结果返回 String result = future.get(); long end = System.currentTimeMillis(); log.info("time: {}", end - start); return result; } }
请求接口:等待2秒后返回
GET http://localhost:8080/task/asyncTaskFuture Accept: application/json
4、@Async + 自定义线程池
package com.example.demo.config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor; import java.util.concurrent.Executor; import java.util.concurrent.ThreadPoolExecutor; /** * 自定义线程池 */ @Configuration public class ExecutorAsyncConfig { @Bean(name = "newAsyncExecutor") public Executor newAsync() { ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor(); // 设置核心线程数 taskExecutor.setCorePoolSize(10); // 线程池维护线程的最大数量,只有在缓冲队列满了以后才会申请超过核心线程数的线程 taskExecutor.setMaxPoolSize(100); // 缓存队列 taskExecutor.setQueueCapacity(50); // 允许的空闲时间,当超过了核心线程数之外的线程在空闲时间到达之后会被销毁 taskExecutor.setKeepAliveSeconds(200); // 异步方法内部线程名称 taskExecutor.setThreadNamePrefix("my-xiaoxiao-AsyncExecutor-"); // 拒绝策略 taskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy()); taskExecutor.initialize(); return taskExecutor; } }
异步任务
package com.example.demo.service; import lombok.extern.slf4j.Slf4j; import org.springframework.scheduling.annotation.Async; import org.springframework.scheduling.annotation.AsyncResult; import org.springframework.stereotype.Service; import java.util.concurrent.Future; @Service @Slf4j public class TaskService { /** * 自定义线程池 执行异步任务 * @throws InterruptedException */ @Async("newAsyncExecutor") public void asyncTaskNewAsync() throws InterruptedException { Thread.sleep(1000 * 2); System.out.println("asyncTaskNewAsync"); } }
控制器
package com.example.demo.controller; import com.example.demo.service.TaskService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.concurrent.CompletableFuture; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; @RestController @RequestMapping("/task") @Slf4j public class TaskController { @Autowired private TaskService taskService; @GetMapping("/asyncTaskNewAsync") public String asyncTaskNewAsync() throws InterruptedException { long start = System.currentTimeMillis(); taskService.asyncTaskNewAsync(); long end = System.currentTimeMillis(); log.info("time: {}", end - start); return "success"; } }
请求接口:无等待,直接返回
GET http://localhost:8080/task/asyncTaskNewAsync Accept: application/json
5、CompletableFuture 实现异步任务
不需要在启动类上加@
EnableAsync
注解,也不需要在方法上加@Async
注解
控制器
package com.example.demo.controller; import com.example.demo.service.TaskService; import lombok.extern.slf4j.Slf4j; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.concurrent.CompletableFuture; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; @RestController @RequestMapping("/task") @Slf4j public class TaskController { @GetMapping("/completableFuture") public String completableFuture(){ long start = System.currentTimeMillis(); // CompletableFuture实现异步任务 CompletableFuture<Void> result = CompletableFuture.runAsync(() -> { try { Thread.sleep(1000 * 2); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println("CompletableFuture"); }); long end = System.currentTimeMillis(); log.info("time: {}", end - start); return "success"; } }
参考