1.配置微信公众服务器

2.提前下好公众号SHA1算法生成安全签名类

/**
 * SHA1 class
 *
 * 计算公众平台的消息签名接口.
 */
public class SHA1 {

	/**
	 * 用SHA1算法生成安全签名
	 * @param token 票据
	 * @param timestamp 时间戳
	 * @param nonce 随机字符串
	 * @param encrypt 密文
	 * @return 安全签名

	 */
	public static String getSHA1(String token, String timestamp, String nonce, String encrypt)
			  {
		try {
			String[] array = new String[] { token, timestamp, nonce, encrypt };
			StringBuffer sb = new StringBuffer();
			// 字符串排序
			Arrays.sort(array);
			for (int i = 0; i < 4; i++) {
				sb.append(array[i]);
			}
			String str = sb.toString();
			// SHA1签名生成
			MessageDigest md = MessageDigest.getInstance("SHA-1");
			md.update(str.getBytes());
			byte[] digest = md.digest();

			StringBuffer hexstr = new StringBuffer();
			String shaHex = "";
			for (int i = 0; i < digest.length; i++) {
				shaHex = Integer.toHexString(digest[i] & 0xFF);
				if (shaHex.length() < 2) {
					hexstr.append(0);
				}
				hexstr.append(shaHex);
			}
			return hexstr.toString();
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}






}

3.创建一个接口，就是配置公众号服务的接口

 //微信公众号验证
    @RequestMapping("openWx/gzhVerification")
    public String gzhVerification(HttpServletRequest request){
        log.info("微信公众号验证");
        String signature=request.getParameter("signature");
        String timestamp=request.getParameter("timestamp");
        String nonce=request.getParameter("nonce");
        String echostr=request.getParameter("echostr");
        String token="token";//这里填基本配置中的token
        String jiami="";
        try {


            jiami= SHA1.getSHA1(token, timestamp, nonce,"");//这里是对三个参数进行加密
          
        if(echostr!=null && jiami.equals(signature)){
            log.info("第一次申请验证成功");
            return  echostr;
        }
        //判断是否是公众号发来的请求
        if(jiami==null || !jiami.equals(signature)){

            log.info("错误的请求");
            return null;
        }
          //----------------------事件推送
            Map<String, String> stringStringMap = parseXml(request);
        //---按钮事件
          if("CLICK".equalsIgnoreCase(stringStringMap.get("Event"))){

              log.info("按钮事件");
            //因为只有一个按钮所以不用判断key了
              String fromUserName = toXML(stringStringMap.get("FromUserName"),stringStringMap.get("ToUserName"));
              log.info("fromUserName:"+fromUserName);
              //发送消息
              return  fromUserName;
              //关注公众号数据
          }else if("subscribe".equalsIgnoreCase(stringStringMap.get("Event")) && stringStringMap.get("EventKey")==null  && stringStringMap.get("Ticket")==null){
              log.info("关注公众号");
              customerWxGzhService._add(stringStringMap.get("FromUserName"),null);

              //取消关注
          }else if("unsubscribe".equalsIgnoreCase(stringStringMap.get("Event"))) {
              log.info("取消关注");

              customerWxGzhService._delete(stringStringMap.get("FromUserName"));

             //二维码关注
          }else if("subscribe".equalsIgnoreCase(stringStringMap.get("Event")) && stringStringMap.get("EventKey")!=null  && stringStringMap.get("Ticket")!=null){

              log.info("二维码关注");
              //获取二维码参数值
              String eventKey =stringStringMap.get("EventKey");
              eventKey= eventKey.substring(8);
              customerWxGzhService._add(stringStringMap.get("FromUserName"),eventKey);
          }

        } catch (Exception e) {
            // TODO Auto-generated catch block

            e.printStackTrace();
        }

        return  null;
    }


    /**
     * dom4j 解析 xml 转换为 map
     * @param request
     * @return
     * @throws Exception
     */
    public static 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>();
        // 从request中取得输入流
        InputStream inputStream = request.getInputStream();
        // 读取输入流
        SAXReader reader = new SAXReader();
        Document document = reader.read(inputStream);
        // 得到xml根元素
        Element root = document.getRootElement();
        // 得到根元素的所有子节点
        List<Element> elementList = root.elements();

        // 遍历所有子节点
        for (Element e : elementList)
            map.put(e.getName(), e.getText());

        // 释放资源
        inputStream.close();
        inputStream = null;
        return map;
    }


    //发送联系我们
    public String toXML(String toUserName,String fromUserName){
        StringBuilder sb = new StringBuilder();
        sb.append("<xml>");
        sb.append("<ToUserName><![CDATA["+toUserName+"]]></ToUserName>");
        sb.append("<FromUserName><![CDATA["+fromUserName+"]]></FromUserName>");
        sb.append("<CreateTime>"+System.currentTimeMillis()/1000+"</CreateTime>");
        sb.append("<MsgType><![CDATA[text]]></MsgType>");
        sb.append("<Content><![CDATA[您好]]></Content>");
        sb.append("</xml>");
        return sb.toString();
    }

公众号事件的提示只有一个接口 就是不断判断Event参数来处理事件，