feat：引入shutdownGracefully()来进行优雅下线，保护存量任务执行完毕

Author: xiaoyumuxi

rpc-core/src/main/java/com/xiaoyu/rpc/core/registry/LocalRegistry.java

@@ -19,4 +19,10 @@ public InetSocketAddress lookupService(String serviceName) {
         System.out.println("LocalRegistry: Looking up " + serviceName);
         return SERVICES.get(serviceName);
     }
+
+    @Override
+    public void clearRegistry() {
+        SERVICES.clear();
+        System.out.println("LocalRegistry: Cleared all services.");
+    }
 }

rpc-core/src/main/java/com/xiaoyu/rpc/core/registry/ServiceRegistry.java

@@ -16,4 +16,9 @@ public interface ServiceRegistry {
      * @param inetSocketAddress 服务地址
      */
     void registerService(String serviceName, InetSocketAddress inetSocketAddress);
+
+    /**
+     * 注销所有服务 (用于优雅下线)
+     */
+    void clearRegistry();
 }

rpc-core/src/main/java/com/xiaoyu/rpc/core/registry/nacos/NacosServiceRegistry.java

@@ -22,4 +22,9 @@ public void registerService(String serviceName, InetSocketAddress inetSocketAddr
             throw new RuntimeException("注册服务失败", e);
         }
     }
+
+    @Override
+    public void clearRegistry() {
+        NacosUtils.clearRegistry();
+    }
 }

rpc-core/src/main/java/com/xiaoyu/rpc/core/server/RpcServer.java

@@ -27,6 +27,16 @@ public RpcServer() {
         // 获取传输层实现
         Transport transport = ExtensionLoader.getExtensionLoader(Transport.class).getExtension(config.getTransport());
         this.transportServer = transport.createServer(this.serverPort);
+
+        // 注册 JVM 关闭挂钩 (优雅下线)
+        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+            log.info("检测到 JVM 关闭信号，正在执行优雅下线...");
+            // 1. 注销服务 (防止新流量进入)
+            serviceRegistry.clearRegistry();
+            // 2. 关闭网络层 (处理完存量请求)
+            transportServer.stop();
+            log.info("优雅下线完成。");
+        }));
     }
 
     public <T> void register(Class<T> interfaceClass, T serviceImpl) {