使用@async实现异步任务

Author: dyc87112

2.x/chapter7-5/src/main/java/com/didispace/chapter75/AsyncTasks.java

@@ -1,40 +1,46 @@
 package com.didispace.chapter75;
 
-import lombok.AllArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.scheduling.annotation.Async;
 import org.springframework.stereotype.Component;
 
 import java.util.Random;
+import java.util.concurrent.CompletableFuture;
 
 @Slf4j
 @Component
-@AllArgsConstructor
 public class AsyncTasks {
 
     public static Random random = new Random();
 
-    public void doTaskOne() throws Exception {
+    @Async
+    public CompletableFuture<String> doTaskOne() throws Exception {
         log.info("开始做任务一");
         long start = System.currentTimeMillis();
         Thread.sleep(random.nextInt(10000));
         long end = System.currentTimeMillis();
         log.info("完成任务一，耗时：" + (end - start) + "毫秒");
+        return CompletableFuture.completedFuture("任务一完成");
     }
 
-    public void doTaskTwo() throws Exception {
+    @Async
+    public CompletableFuture<String> doTaskTwo() throws Exception {
         log.info("开始做任务二");
         long start = System.currentTimeMillis();
         Thread.sleep(random.nextInt(10000));
         long end = System.currentTimeMillis();
         log.info("完成任务二，耗时：" + (end - start) + "毫秒");
+        return CompletableFuture.completedFuture("任务二完成");
     }
 
-    public void doTaskThree() throws Exception {
+    @Async
+    public CompletableFuture<String>  doTaskThree() throws Exception {
         log.info("开始做任务三");
         long start = System.currentTimeMillis();
         Thread.sleep(random.nextInt(10000));
         long end = System.currentTimeMillis();
         log.info("完成任务三，耗时：" + (end - start) + "毫秒");
+        return CompletableFuture.completedFuture("任务三完成");
     }
 
 }

2.x/chapter7-5/src/main/java/com/didispace/chapter75/Chapter75Application.java

@@ -2,7 +2,9 @@
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableAsync;
 
+@EnableAsync
 @SpringBootApplication
 public class Chapter75Application {
 

2.x/chapter7-5/src/test/java/com/didispace/chapter75/Chapter75ApplicationTests.java

@@ -5,6 +5,9 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Future;
+
 @Slf4j
 @SpringBootTest
 public class Chapter75ApplicationTests {
@@ -14,9 +17,17 @@ public class Chapter75ApplicationTests {
 
     @Test
     public void test() throws Exception {
-        asyncTasks.doTaskOne();
-        asyncTasks.doTaskTwo();
-        asyncTasks.doTaskThree();
+        long start = System.currentTimeMillis();
+
+        CompletableFuture<String> task1 = asyncTasks.doTaskOne();
+        CompletableFuture<String> task2 = asyncTasks.doTaskTwo();
+        CompletableFuture<String> task3 = asyncTasks.doTaskThree();
+
+        CompletableFuture.allOf(task1, task2, task3).join();
+
+        long end = System.currentTimeMillis();
+
+        log.info("任务全部完成，总耗时：" + (end - start) + "毫秒");
     }
 
 }