Token verification and message processing methods for WeChat public platform development

/**
 *
 * @Description: 微信消息处理以及用户分组
 * @author zhangjun
 * @date 2014-1-7 上午10:51:51
 */
public class WeiXinMessageAction extends BaseAction{
    /**
     *
     */
    private static final long serialVersionUID = 1L;
       
    private IFeWeiXinMessageService weiXinExternalService;
       
    private String wxNo;
       
    public String responseMessgaeInfo(){
        Boolean isGet = request.getMethod().equalsIgnoreCase("GET");
        if(isGet){
            validateSignature();
        }else{
            saveWxMessage();
        }
        return null;
    }
    /**
     *
     * @Description: 接收post保存接受的消息 只保存MsgType类型为text信息
     * @param   
     * @return void
     * @throws
     */
    private void saveWxMessage(){
        InputStream inputStream;
        try {
            request.setCharacterEncoding("UTF-8");
            Document doc = null;
            SAXReader reader = new SAXReader();
            inputStream = request.getInputStream();
            doc = reader.read(inputStream);
            Element root = doc.getRootElement();
            String toUserName = root.element("ToUserName").getTextTrim();
            String fromUserName = root.element("FromUserName").getTextTrim();
            String content = root.element("Content").getTextTrim();
            String msgType=root.element("MsgType").getTextTrim();
            String msgId=root.element("MsgId").getTextTrim();
            String createTime=root.element("CreateTime").getTextTrim();
            //只保存文本消息
            //时间
            System.out.println("接收消息内容:"+content+"-----------------msgType:"+msgType);
            if(WeiXinMsgType.TEXT.type.equals(msgType)){
                weiXinExternalService.addWxMessage(toUserName, fromUserName, content, msgType, msgId, formatTime(createTime));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
       
    /**
     *
     * @Description: 传入的CreateTime转换成long类型
     * @param @param createTime
     * @param @return  
     * @return Date
     * @throws
     */
    private   Date formatTime(String createTime) {
        long msgCreateTime = Long.parseLong(createTime) * 1000L;
        return new Date(msgCreateTime);
    }
       
    /**
     *
     * @Description: 校验微信签名
     * @param   
     * @return void
     * @throws
     */
    private void validateSignature(){
        PrintWriter out = null;
        try {
            String signature = request.getParameter("signature");
            String timestamp = request.getParameter("timestamp");
            String nonce = request.getParameter("nonce");
            out = response.getWriter();
            if (checkSignature(signature, timestamp, nonce)) {
                out.print(request.getParameter("echostr"));
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            out.close();
            out = null;
        }
    }
       
    /**
     *
     * @Description: 判断token是否合法
     * @param @param signature
     * @param @param timestamp
     * @param @param nonce
     * @param @return  
     * @return boolean
     * @throws
     */
    private  boolean checkSignature(String signature, String timestamp, String nonce) {
            //根据微信账号获取token并校验
            Map<String,Object> map=new HashMap<String,Object>();
            map.put("wxNo", wxNo);
            WeiXinMasterConfig  masterConfig= weiXinExternalService.selectWeiXinMasterConfig(map);
            if(masterConfig==null){
                return false;
            }
            String[] arr = new String[] {masterConfig.getWxToken(), timestamp, nonce };
            Arrays.sort(arr);
            StringBuilder content = new StringBuilder();
            for (int i = 0; i < arr.length; i++) {
                content.append(arr[i]);
            }
            MessageDigest md = null;
            String tmpStr = null;
            try {
                md = MessageDigest.getInstance("SHA-1");
                byte[] digest = md.digest(content.toString().getBytes());
                tmpStr = byteToStr(digest);
            } catch (NoSuchAlgorithmException e) {
                e.printStackTrace();
            }
            content = null;
            return tmpStr != null ? tmpStr.equals(signature.toUpperCase()) : false;
    }
    // 将字节转换为十六进制字符串
    private static String byteToHexStr(byte ib) {
        char[] Digit = { &#39;0&#39;, &#39;1&#39;, &#39;2&#39;, &#39;3&#39;, &#39;4&#39;, &#39;5&#39;, &#39;6&#39;, &#39;7&#39;, &#39;8&#39;, &#39;9&#39;, &#39;A&#39;,
                &#39;B&#39;, &#39;C&#39;, &#39;D&#39;, &#39;E&#39;, &#39;F&#39; };
        char[] ob = new char[2];
        ob[0] = Digit[(ib >>> 4) & 0X0F];
        ob[1] = Digit[ib & 0X0F];
        String s = new String(ob);
        return s;
    }
    // 将字节数组转换为十六进制字符串
    private static String byteToStr(byte[] bytearray) {
        String strDigest = "";
        for (int i = 0; i < bytearray.length; i++) {
            strDigest += byteToHexStr(bytearray[i]);
        }
        return strDigest;
    }