微信小程序实现websocket步骤:
后台:
1. 添加maven依赖 2. 创建握手 3. 创建处理器 4. spring配置(xml配置或javabean方式配置任选一种)
微信小程序:
1. 书写连接
java后台
1.添加maven依赖
<!-- websocket --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-websocket</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-messaging</artifactId> <version>${spring.version}</version> </dependency> <!-- 其中spring版本 --> <!-- 注意spring版本一定要为4以上版本 --> <spring.version>4.3.7.RELEASE</spring.version>
2.创建握手
package com.ahutshop.websocket; import java.util.Map; import javax.servlet.http.HttpServletRequest; import org.springframework.http.server.ServerHttpRequest; import org.springframework.http.server.ServerHttpResponse; import org.springframework.http.server.ServletServerHttpRequest; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.server.HandshakeInterceptor; /** * 此类用来获取登录用户信息并交由websocket管理 */ public class MyWebSocketInterceptor implements HandshakeInterceptor { @Override public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse arg1, WebSocketHandler arg2, Map<String, Object> arg3) throws Exception { // 将ServerHttpRequest转换成request请求相关的类，用来获取request域中的用户信息 if (request instanceof ServletServerHttpRequest) { ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request; HttpServletRequest httpRequest = servletRequest.getServletRequest(); } System.out.println("连接到我了"); return true; } @Override public void afterHandshake(ServerHttpRequest arg0, ServerHttpResponse arg1, WebSocketHandler arg2, Exception arg3) { // TODO Auto-generated method stub } }
3.创建处理器
package com.ahutshop.websocket; import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.springframework.web.socket.CloseStatus; import org.springframework.web.socket.TextMessage; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.WebSocketMessage; import org.springframework.web.socket.WebSocketSession; public class WebSocketPushHandler implements WebSocketHandler { private static final List<WebSocketSession> users = new ArrayList<>(); // 用户进入系统监听 @Override public void afterConnectionEstablished(WebSocketSession session) throws Exception { System.out.println("成功进入了系统。。。"); users.add(session); sendMessagesToUsers(new TextMessage("今天晚上服务器维护,请注意")); } // @Override public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception { // 将消息进行转化，因为是消息是json数据，可能里面包含了发送给某个人的信息，所以需要用json相关的工具类处理之后再封装成TextMessage， // 我这儿并没有做处理，消息的封装格式一般有{from:xxxx,to:xxxxx,msg:xxxxx}，来自哪里，发送给谁，什么消息等等 // TextMessage msg = (TextMessage)message.getPayload(); // 给所有用户群发消息 //sendMessagesToUsers(msg); // 给指定用户群发消息 //sendMessageToUser(userId, msg); } // 后台错误信息处理方法 @Override public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception { } // 用户退出后的处理，不如退出之后，要将用户信息从websocket的session中remove掉，这样用户就处于离线状态了，也不会占用系统资源 @Override public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception { if (session.isOpen()) { session.close(); } users.remove(session); System.out.println("安全退出了系统"); } @Override public boolean supportsPartialMessages() { return false; } /** * 给所有的用户发送消息 */ public void sendMessagesToUsers(TextMessage message) { for (WebSocketSession user : users) { try { // isOpen()在线就发送 if (user.isOpen()) { user.sendMessage(message); } } catch (IOException e) { e.printStackTrace(); } } } /** * 发送消息给指定的用户 */ public void sendMessageToUser(String userId, TextMessage message) { for (WebSocketSession user : users) { if (user.getAttributes().get("").equals(userId)) { try { // isOpen()在线就发送 if (user.isOpen()) { user.sendMessage(message); } } catch (IOException e) { e.printStackTrace(); } } } } }
4.spring配置