相信很多人对微信开发已经不那么陌生，我也是从一个微信开发的菜鸟经过各种问题的折磨，然后去搜索引擎搜索各种文章阅读，但是基本都是零散的资料，没有一个统一、系统的阐述微信应用如何开发。作者结合自己的实际开发经验，归纳整理出来分享给微信开发的入门者或正在研究的开发者。
这篇文章主要阐述如何搭建一个微信开发平台。古人云：“磨刀不负砍才工”。我们开发应用也需要准备一些必要的条件。
准备工作
1. 下载 Jdk1.7 安装
2. 下载 Tomcat 7.0
3. 下载 Myeclipse 6.5
4. 下载 Json-lib第三方jar .
1. 申请一个公网IP地址，发布自己的应用。
例如： 192.168.1.102
2. 打开myeclipse 创建一个工程
如下图所示：
3. 创建一个微信应用接入Servlet类
JAVA实现类 ：WeixinServlet
package com.wx.servlet;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;import java.util.Arrays;import java.util.logging.Logger;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import net.sf.json.JSONObject;import net.sf.json.xml.XMLSerializer; /** * @author haibing.xiao * @since jdk1.6 * @version 1.0 */public class WeixinServlet extends HttpServlet{private Logger log =Logger.getLogger(this.getClass().getName());private static final long serialVersionUID = 1L;private String Token;private String echostr;@Overrideprotected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { connect(request,response);}@Overrideprotected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {message(request,response);} /** *@author haibing.xiao *@return *@exception *@param * * <p>接入连接生效验证</p> */private void connect(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{log.info("RemoteAddr: "+ request.getRemoteAddr());log.info("QueryString: "+ request.getQueryString()); if(!accessing(request, response)){ log.info("服务器接入失败......."); return ; }String echostr=getEchostr();if(echostr!=null && !"".equals(echostr)){log.info("服务器接入生效..........");response.getWriter().print(echostr);//完成相互认证}}/** * @author haibing.xiao * Date 2013-05-29 * @return boolean * @exception ServletException, IOException * @param * *<p>用来接收微信公众平台的验证</p> */private boolean accessing(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String signature = request.getParameter("signature");String timestamp = request.getParameter("timestamp");String nonce = request.getParameter("nonce");String echostr = request.getParameter("echostr");if( isEmpty(signature)){return false;}if(isEmpty(timestamp)){return false;}if(isEmpty(nonce)){return false;}if(isEmpty(echostr)){return false;}String[] ArrTmp = { Token, timestamp, nonce };Arrays.sort(ArrTmp);StringBuffer sb = new StringBuffer();for (int i = 0; i < ArrTmp.length; i++) {sb.append(ArrTmp[i]);}String pwd = Encrypt(sb.toString()); log.info("signature:"+signature+"timestamp:"+timestamp+"nonce:"+nonce+"pwd:"+pwd+"echostr:"+echostr); if(trim(pwd).equals(trim(signature))){ this.echostr =echostr; return true; }else{ return false; }}private String Encrypt(String strSrc) {MessageDigest md = null;String strDes = null;byte[] bt = strSrc.getBytes();try {md = MessageDigest.getInstance("SHA-1");md.update(bt);strDes = bytes2Hex(md.digest()); //to HexString} catch (NoSuchAlgorithmException e) {System.out.println("Invalid algorithm.");return null;}return strDes;}public String bytes2Hex(byte[] bts) {String des = "";String tmp = null;for (int i = 0; i < bts.length; i++) {tmp = (Integer.toHexString(bts[i] & 0xFF));if (tmp.length() == 1) {des += "0";}des += tmp;}return des;} public String getEchostr(){return echostr;}/** *@author haibing.xiao *@return *@exception ServletException, IOException *@param * * <p>XML组装组件</p> */ private void message(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{ InputStream is = request.getInputStream();// 取HTTP请求流长度int size = request.getContentLength();// 用于缓存每次读取的数据byte[] buffer = new byte[size];// 用于存放结果的数组byte[] xmldataByte = new byte[size];int count = 0;int rbyte = 0;// 循环读取while (count < size) { // 每次实际读取长度存于rbyte中rbyte = is.read(buffer); for(int i=0;i<rbyte;i++) {xmldataByte[count + i] = buffer[i];}count += rbyte;}is.close();String requestStr = new String(xmldataByte, "UTF-8");try{manageMessage(requestStr,request,response);}catch(Exception e){e.printStackTrace();}} /** * @author haibing.xiao * @return * @exception ServletException, IOException * @param * * <p>业务转发组件</p> * */ private void manageMessage(String requestStr,HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException{ String responseStr; try { XMLSerializer xmlSerializer=new XMLSerializer(); JSONObject jsonObject =(JSONObject) xmlSerializer.read(requestStr); String event =jsonObject.getString("Event"); String msgtype =jsonObject.getString("MsgType"); if("CLICK".equals(event) && "event".equals(msgtype)){ //菜单click事件 String eventkey =jsonObject.getString("EventKey"); if("hytd_001".equals(eventkey)){ // hytd_001 这是好友团队按钮的标志值 jsonObject.put("Content", "欢迎使用好友团队菜单click按钮."); } } responseStr =creatRevertText(jsonObject);//创建XML log.info("responseStr:"+responseStr); OutputStream os =response.getOutputStream(); os.write(responseStr.getBytes("UTF-8"));} catch (Exception e) {e.printStackTrace();}}private String creatRevertText(JSONObject jsonObject){ StringBuffer revert =new StringBuffer(); revert.append("<xml>"); revert.append("<ToUserName><![CDATA["+jsonObject.get("ToUserName")+"]]></ToUserName>"); revert.append("<FromUserName><![CDATA["+jsonObject.get("FromUserName")+"]]></FromUserName>"); revert.append("<CreateTime>"+jsonObject.get("CreateTime")+"</CreateTime>"); revert.append("<MsgType><![CDATA[text]]></MsgType>"); revert.append("<Content><![CDATA["+jsonObject.get("Content")+"]]></Content>"); revert.append("<FuncFlag>0</FuncFlag>"); revert.append("</xml>"); return revert.toString(); }@Overridepublic void init() throws ServletException {Token="test123";} private boolean isEmpty(String str){return null ==str || "".equals(str) ? true :false;}private String trim(String str){return null !=str ? str.trim() : str;}}4. 本地部署应用 访问http://localhost:端口号/上下文/wenxin
5 .申请成为开发者
访问 http://mp.weixin.qq.com ，开启开发者模式。填入URL和taken，申请成功，如下所示：
