diff --git a/docs-site/docs/.vitepress/config.ts b/docs-site/docs/.vitepress/config.ts
index f829a4e..70911f9 100644
--- a/docs-site/docs/.vitepress/config.ts
+++ b/docs-site/docs/.vitepress/config.ts
@@ -85,7 +85,9 @@ export default defineConfig({
       '/server/': [
         { text: 'API 速查', link: '/server/api' },
         { text: 'Go Server SDK', link: '/server/go-sdk' },
+        { text: 'Java Server SDK', link: '/server/java-sdk' },
         { text: 'Python Server SDK', link: '/server/python-sdk' },
+        { text: 'WebSocket 协议', link: '/server/websocket' },
         { text: '错误码', link: '/server/errors' },
       ],
     },
diff --git a/docs-site/docs/demo/index.md b/docs-site/docs/demo/index.md
index 25d415d..08930bf 100644
--- a/docs-site/docs/demo/index.md
+++ b/docs-site/docs/demo/index.md
@@ -24,32 +24,76 @@
     />
     <p><a href="/demo/rn-chat-demo.apk">下载 APK</a></p>
   </div>
+
+  <div class="demo-card">
+    <h2>Flutter Chat Demo</h2>
+    <p>Flutter 端 IM + 推送演示，支持 Android / iOS 双端。</p>
+    <img
+      alt="Flutter Chat Demo 下载二维码"
+      src="https://api.qrserver.com/v1/create-qr-code/?size=220x220&data=https%3A%2F%2Fdev.xuqinmin.com%2Fdocs%2Fdemo%2Fflutter-chat-demo.apk"
+    />
+    <p><a href="/demo/flutter-chat-demo.apk">下载 APK（Android）</a></p>
+  </div>
 </div>
 
 ## Web
 
 <div class="demo-grid">
   <div class="demo-card">
-    <h2>tenant-platform</h2>
-    <p>租户开放平台，登录后可直接进入应用、IM、版本管理等页面。</p>
+    <h2>租户控制台</h2>
+    <p>登录后可直接进入应用管理、IM、推送管理、版本管理等页面。</p>
     <p>
       <a href="https://dev.xuqinmin.com" target="_blank" rel="noreferrer">打开控制台</a>
-      <span style="padding:0 8px;">·</span>
+    </p>
+  </div>
+
+  <div class="demo-card">
+    <h2>IM 演示页</h2>
+    <p>基于 Vue3 SDK 的在线 IM 聊天演示，可直接体验消息收发。</p>
+    <p>
       <a href="https://dev.xuqinmin.com/apps/ak_demo_chat/im" target="_blank" rel="noreferrer">打开 IM 演示页</a>
     </p>
   </div>
 
   <div class="demo-card">
-    <h2>docs-site 快速入口</h2>
-    <p>先看快速开始，再按平台页接入。</p>
+    <h2>H5 SDK 在线演示</h2>
+    <p>纯 JS 环境下的 IM 接入示例，框架无关，可查看源码参考。</p>
     <p>
-      <a href="/guide/quickstart">快速开始</a>
+      <a href="/h5/">H5 SDK 文档</a>
       <span style="padding:0 8px;">·</span>
       <a href="/server/api">API 速查</a>
     </p>
   </div>
 </div>
 
+## 服务端示例
+
+<div class="demo-grid">
+  <div class="demo-card">
+    <h2>Go 服务端示例</h2>
+    <p>使用 Go Server SDK 发送 IM 消息和 Push 推送的完整示例。</p>
+    <p>
+      <a href="/server/go-sdk">Go SDK 文档</a>
+    </p>
+  </div>
+
+  <div class="demo-card">
+    <h2>Java 服务端示例</h2>
+    <p>使用 Java Server SDK 集成 IM 和 Push 的 Spring Boot 示例。</p>
+    <p>
+      <a href="/server/java-sdk">Java SDK 文档</a>
+    </p>
+  </div>
+
+  <div class="demo-card">
+    <h2>Python 服务端示例</h2>
+    <p>使用 Python Server SDK 发送消息和推送的示例脚本。</p>
+    <p>
+      <a href="/server/python-sdk">Python SDK 文档</a>
+    </p>
+  </div>
+</div>
+
 <style>
 .demo-grid {
   display: grid;
diff --git a/docs-site/docs/guide/quickstart.md b/docs-site/docs/guide/quickstart.md
index a53ffce..0e28ce9 100644
--- a/docs-site/docs/guide/quickstart.md
+++ b/docs-site/docs/guide/quickstart.md
@@ -10,6 +10,8 @@
 
 ## 2. 选择你的平台
 
+### 客户端 SDK
+
 | 平台 | 推荐接入方式 |
 |------|------------|
 | Android | [Android SDK →](/android/) |
@@ -17,6 +19,17 @@
 | React Native | [RN SDK →](/rn/) |
 | Vue3 / Web | [Vue3 SDK →](/vue3/) |
 | HarmonyOS | [HarmonyOS SDK →](/harmony/) |
+| Flutter | [Flutter SDK →](/flutter/) |
+| 微信小程序 | [小程序 SDK →](/miniprogram/) |
+| H5 / 纯 JS | [H5 SDK →](/h5/) |
+
+### 服务端 SDK
+
+| 语言 | 接入方式 |
+|------|---------|
+| Go | [Go Server SDK →](/server/go-sdk) |
+| Java | [Java Server SDK →](/server/java-sdk) |
+| Python | [Python Server SDK →](/server/python-sdk) |
 
 ## 3. 接入流程
 
diff --git a/docs-site/docs/server/java-sdk.md b/docs-site/docs/server/java-sdk.md
new file mode 100644
index 0000000..ec6e447
--- /dev/null
+++ b/docs-site/docs/server/java-sdk.md
@@ -0,0 +1,144 @@
+# Java Server SDK
+
+XuqmGroup 服务端 Java SDK，提供 IM 消息发送、群管理、Push 推送等能力。
+
+---
+
+## 安装
+
+Maven 在 `pom.xml` 中添加：
+
+```xml
+<repository>
+  <id>nexus-xuqm</id>
+  <url>https://nexus.xuqinmin.com/repository/android/</url>
+</repository>
+
+<dependency>
+  <groupId>com.xuqm</groupId>
+  <artifactId>xuqm-server-sdk</artifactId>
+  <version>0.1.0</version>
+</dependency>
+```
+
+Gradle：
+
+```kotlin
+repositories {
+    maven { url = uri("https://nexus.xuqinmin.com/repository/android/") }
+}
+
+dependencies {
+    implementation("com.xuqm:xuqm-server-sdk:0.1.0")
+}
+```
+
+---
+
+## 初始化
+
+```java
+import com.xuqm.sdk.server.XuqmServerClient;
+import com.xuqm.sdk.server.XuqmServerConfig;
+
+XuqmServerClient client = new XuqmServerClient(XuqmServerConfig.builder()
+    .baseUrl("https://dev.xuqinmin.com")
+    .appId("your_app_id")
+    .appSecret("your_app_secret")
+    .build());
+```
+
+> 服务端 SDK 需要 `appSecret` 用于 HMAC 签名，`appSecret` 绝不下发到客户端。
+
+---
+
+## 发送消息
+
+```java
+import com.xuqm.sdk.server.model.SendMessageRequest;
+import com.xuqm.sdk.server.model.ImMessage;
+
+ImMessage msg = client.sendMessage(SendMessageRequest.builder()
+    .toId("user_002")
+    .chatType("SINGLE")
+    .msgType("TEXT")
+    .content("Hello from Java SDK!")
+    .build());
+
+System.out.println("消息已发送: " + msg.getId());
+```
+
+### 发送群消息
+
+```java
+ImMessage msg = client.sendMessage(SendMessageRequest.builder()
+    .toId("group_xxx")
+    .chatType("GROUP")
+    .msgType("TEXT")
+    .content("大家好")
+    .build());
+```
+
+### 撤回消息
+
+```java
+client.revokeMessage("message_id");
+```
+
+---
+
+## 群管理
+
+```java
+import com.xuqm.sdk.server.model.*;
+
+// 创建群组
+ImGroup group = client.createGroup(CreateGroupRequest.builder()
+    .name("项目讨论")
+    .memberIds(List.of("user_001", "user_002"))
+    .build());
+
+// 添加群成员
+client.addGroupMember("group_xxx", "user_003");
+
+// 移除群成员
+client.removeGroupMember("group_xxx", "user_003");
+
+// 获取群列表
+List<ImGroup> groups = client.listGroups();
+
+// 获取群成员
+List<ImUser> members = client.listGroupMembers("group_xxx");
+```
+
+---
+
+## Push 推送
+
+```java
+import com.xuqm.sdk.server.model.SendPushRequest;
+
+client.sendPush(SendPushRequest.builder()
+    .userId("user_001")
+    .title("新消息")
+    .body("你有一条未读消息")
+    .payload("{\"chatId\":\"user_002\"}")
+    .build());
+```
+
+---
+
+## 错误处理
+
+```java
+import com.xuqm.sdk.server.exception.XuqmApiException;
+
+try {
+    ImMessage msg = client.sendMessage(request);
+} catch (XuqmApiException e) {
+    System.err.printf("API 错误: status=%d, code=%d, message=%s%n",
+        e.getHttpStatus(), e.getCode(), e.getMessage());
+}
+```
+
+[→ Server API 文档](/server/api)