🔄Update: 基于 Async 实现线程池

README.md

@@ -1,5 +1,18 @@
 # 使用 `@Async` 实现线程池
 
+```mermaid
+graph TD
+    A[调用者调用异步方法] --> B[Spring AOP 代理拦截方法调用]
+    B --> C{方法是否为 @Async?}
+    C -->|是| D[封装为 FutureTask 或 Runnable]
+    C -->|否| E[按正常方式执行]
+    D --> F[提交到线程池 TaskExecutor]
+    F --> G[线程池分配一个线程]
+    G --> H[JVM 创建线程并执行任务]
+    H --> I[任务执行完毕，返回结果]
+    I --> J[调用者通过 Future 获取结果]
+```
+
 ## 前置知识
 
 ### **`@Async`**

src/main/java/cn/hezhaohui/threadpool/conifg/AsyncConfig.java

@@ -0,0 +1,27 @@
+package cn.hezhaohui.threadpool.conifg;
+
+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.Executor;
+
+/**
+ * 异步配置类
+ */
+@Configuration
+@EnableAsync
+public class AsyncConfig {
+
+    @Bean(name = "customThreadPool")
+    public Executor customThreadPool() {
+        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
+        executor.setCorePoolSize(5);
+        executor.setMaxPoolSize(10);
+        executor.setQueueCapacity(100);
+        executor.setThreadNamePrefix("Custom-Async-");
+        executor.initialize();
+        return executor;
+    }
+}

src/main/java/cn/hezhaohui/threadpool/service/AsyncService.java

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+package cn.hezhaohui.threadpool.service;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Service;
+
+import java.util.Random;
+import java.util.UUID;
+import java.util.concurrent.CountDownLatch;
+
+@Service
+@Slf4j
+public class AsyncService {
+
+    @Async("customThreadPool")
+    public void asyncPrint() {
+        String id = UUID.randomUUID().toString().substring(0, 5);
+        int sleepSeconds = new Random().nextInt(15);
+        log.info("[Thread {}] Called, waiting {} seconds", id, sleepSeconds);
+        try {
+            Thread.sleep(sleepSeconds * 1000L);
+            log.info("[Thread {}] Wait completed after {} seconds", id, sleepSeconds);
+        } catch (InterruptedException e) {
+            log.error("[Thread {}] Interrupted during wait", id, e);
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    @Async("customThreadPool")
+    public void asyncPrint(CountDownLatch latch) {
+        String id = UUID.randomUUID().toString().substring(0, 5);
+        int sleepSeconds = new Random().nextInt(15);
+        log.info("[Thread {}] ⚠️ Called, waiting {} seconds", id, sleepSeconds);
+        try {
+            Thread.sleep(sleepSeconds * 1000L);
+            log.info("[Thread {}] ✅ Wait completed after {} seconds", id, sleepSeconds);
+        } catch (InterruptedException e) {
+            log.error("[Thread {}] Interrupted during wait", id, e);
+            Thread.currentThread().interrupt();
+        } finally {
+            latch.countDown();
+        }
+    }
+}

src/test/java/cn/hezhaohui/threadpool/service/AsyncServiceTest.java

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+package cn.hezhaohui.threadpool.service;
+
+import jakarta.annotation.Resource;
+import lombok.extern.slf4j.Slf4j;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+import java.util.concurrent.CountDownLatch;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@SpringBootTest
+@Slf4j
+class AsyncServiceTest {
+
+    @Resource
+    private AsyncService asyncService;
+
+    @Test
+    void asyncPrint() throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(15);
+        for (int i = 0; i < 200; i++) {
+            asyncService.asyncPrint(latch);
+        }
+        log.info("\n[+++ All Tasks Commited +++]\n");
+        latch.await();
+        log.info("\n[=== All Tasks Completed ===]\n");
+    }
+}