微信开发--入门（二）

微信菜单自定义推送事件是一个post方式提交的请求， 该post的URL是进入“服务器配置（用于接收用户信息）”配置的URL中。

在成为开发者时的验证URL有效性，是进入URL的get方式。 而菜单自定义推送事件是进入URL的POST方式。

菜单的推送事件，发送的请求是xml格式的String， 在java端首先要把String转化成xml，读取里面的参数，然后对相应的逻辑，最后返回的也是xml格式的String，这样微信才知道要怎么显示消息。

String 与xml的转化可以用dom4j

/*
 * Copyright 2012-2012 imeiya.com All right reserved. This software is the
 * confidential and proprietary information of imeiya.com ("Confidential
 * Information"). You shall not disclose such Confidential Information and shall
 * use it only in accordance with the terms of the license agreement you entered
 * into with imeiya.com.
 */
package com.lehuo.app.ju.weixin;

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.lehuo.app.ju.tb.TbBaseAction;

/**
 * 类IndexAction.java的实现描述：TODO 类实现描述 
 * @author chenyao 2014-1-17 上午10:43:33
 */
@Controller
public class IndexAction extends TbBaseAction{

    @RequestMapping(value="/index.html", method = RequestMethod.GET)
    public void doGet(HttpServletRequest request, HttpServletResponse response, ModelMap model) throws IOException {
        String echostr = request.getParameter("echostr");
        response.getWriter().write(echostr);
    }
    
    @RequestMapping(value="/index.html", method = RequestMethod.POST)
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException {
        // 将请求、响应的编码均设置为UTF-8（防止中文乱码）
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");
        // 调用核心业务类接收消息、处理消息
        String respMessage = processRequest(request);
        // 响应消息
        PrintWriter out;
        try {
            out = response.getWriter();
            out.write(respMessage);
            out.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private String processRequest(HttpServletRequest request) {
        String respMessage = null;
        try {// 默认返回的文本消息内容
            String respContent = "请求处理异常，请稍候尝试！";
            Map<String, String> requestMap = parseXml(request);         
            // 发送方帐号（open_id）
            String fromUserName = requestMap.get("FromUserName");;
            // 公众帐号
            String toUserName =  requestMap.get("ToUserName");
            // 消息类型
            String msgType = requestMap.get("MsgType");
            // 回复文本消息
            TextMessage textMessage = new TextMessage();
            textMessage.setToUserName(fromUserName);
            textMessage.setFromUserName(toUserName);
            textMessage.setCreateTime(new Date());
            textMessage.setMsgType(MessageUtil.RESP_MESSAGE_TYPE_TEXT);
            textMessage.setFuncFlag(0);
            // 文本消息
            if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_TEXT)) {
                respContent = "您发送的是文本消息！";
            }
            // 图片消息
            else if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_IMAGE)) {
                respContent = "您发送的是图片消息！";
            }
            // 地理位置消息
            else if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_LOCATION)) {
                respContent = "您发送的是地理位置消息！";
            }
            // 链接消息
            else if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_LINK)) {
                respContent = "您发送的是链接消息！";
            }
            // 音频消息
            else if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_VOICE)) {
                respContent = "您发送的是音频消息！";
            }
            // 事件推送
            else if (msgType.equals(MessageUtil.REQ_MESSAGE_TYPE_EVENT)) {
                // 事件类型
                String eventType = requestMap.get("Event");
                // 订阅
                if (eventType.equals(MessageUtil.EVENT_TYPE_SUBSCRIBE)) {
                    respContent = "谢谢您的关注！";
                }
                // 取消订阅
                else if (eventType.equals(MessageUtil.EVENT_TYPE_UNSUBSCRIBE)) {
                    // TODO 取消订阅后用户再收不到公众号发送的消息，因此不需要回复消息
                }
                // 自定义菜单点击事件
                else{
                    String eventKey = requestMap.get("EventKey");
                    respContent = "event"+eventKey==null?"":eventKey+"__eventType"+eventType;
                    // TODO 自定义菜单权没有开放，暂不处理该类消息 EventKey
                    /*
                    if(eventKey.equalsIgnoreCase("20_PROMANAGE")){
                        respContent = "项目管理";
                    }
                    else if(eventKey.equalsIgnoreCase("30_ORGANIZATION")){
                        respContent = "机构运作";
                    }
                    else if(eventKey.equalsIgnoreCase("01_WAITING")){
                        respContent = "待办工单";
                    }
                    else if(eventKey.equalsIgnoreCase("02_FINISH")){
                        respContent = "已办工单";
                    }
                    else if(eventKey.equalsIgnoreCase("03_MYJOB")){
                        respContent = "我的工单";
                    }
                    else if(eventKey.equalsIgnoreCase("04_MESSAGEBOX")){
                        respContent = "公告消息箱";
                    }
                    else if(eventKey.equalsIgnoreCase("05_SIGN")){
                        respContent = "签到";
                    }*/
                }
            }
            textMessage.setContent(respContent);
            respMessage = Object2XmlString(textMessage);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return respMessage;
    }
    
    
    @SuppressWarnings("unchecked")
    private Map<String, String> parseXml(HttpServletRequest request) throws Exception {
        // 将解析结果存储在HashMap中
        Map<String, String> map = new HashMap<String, String>();
        InputStream is = request.getInputStream();
        SAXReader reader = new SAXReader();
        Document doc = reader.read(is);
        Element root = doc.getRootElement();
        List<Element> list = root.elements();
        // 遍历所有子节点
        for (Element el : list){
            map.put( el.getName(), el.getText());
        }
        // 释放资源
        is.close();
        is = null;
        return map;
    }
    
    
    /**
     * 将对象转换为xml字符串
     */

    public String Object2XmlString(Object object) {
      return "<xml><ToUserName><![CDATA[测试账号]]></ToUserName><FromUserName><![CDATA[测试账号]]></FromUserName><CreateTime>12345678</CreateTime><MsgType><![CDATA[text]]></MsgType><Content><![CDATA[试试看效果]]></Content></xml>";
    }
    
}