微信公众号关注回调

@RequestMapping(value = "/xxx/onWxMsg")
    public String checkWxToken(@RequestParam(value = "signature", required = false) String signature,
                               @RequestParam(value = "timestamp", required = false) String timestamp,
                               @RequestParam(value = "echostr", required = false) String echostr,
                               @RequestBody(required = false) WxServiceMsgDto wxServiceMsgDto) {
        if (StringUtils.isNotEmpty(echostr)) {
           // 用于微信校验接口存在性，必须返回echostr
            return echostr;
        }
        // 只处理订阅与取消订阅消息
        if (null != wxServiceMsgDto && StringUtils.isNotEmpty(wxServiceMsgDto.getMsgType()) &&
                StringUtils.isNotEmpty(wxServiceMsgDto.getEvent())) {
            String msgType = wxServiceMsgDto.getMsgType();
            String event = wxServiceMsgDto.getEvent();
            boolean isSubcribe = WxMessageType.EVENT.getCode().equals(msgType) &&
                    (WxEeventType.SUBSCRIBE.getCode().equals(event)
                            || WxEeventType.UNSUBSCRIBE.getCode().equals(event));
            if (isSubcribe) {
                WxEeventType wxEeventType = WxEeventType.SUBSCRIBE.getCode().equals(event) ? WxEeventType.SUBSCRIBE : WxEeventType.UNSUBSCRIBE;
                wxService.onFollowCallback(wxServiceMsgDto, wxEeventType);
            }
        }
   。。。。。。
}

@XmlRootElement(name = "xml")
@XmlAccessorType(XmlAccessType.FIELD)
@Data
public class WxServiceMsgDto {

     @XmlElement(name = "Event")
     private String event;

     @XmlElement(name = "Content")
     private String content;

     @XmlElement(name = "MsgType")
     private String msgType;

     @XmlElement(name = "ToUserName")
     private String toUserName;

     
     /**
      * fromUserName为关注人的openId
     **/

     @XmlElement(name = "FromUserName")
     private String fromUserName;

     @XmlElement(name="CreateTime")
     private String createTime;
}

@Getter
public enum WxEeventType {
    /**
     * 关注公众号
     */
    SUBSCRIBE("subscribe"),
    /**
     * 取消关注公众号
     */
    UNSUBSCRIBE("unsubscribe");

    private String code;

    WxEeventType(String code) {
        this.code = code;
    }
}

@Getter
public enum WxMessageType {

    /**
     * 事件类型，比如订阅与取消订阅
     */
    EVENT("event"),
    /**
     * 向公众号发送的文字消息
     */
    TEXT("text");

    private String code;

    WxMessageType(String code) {
        this.code = code;
    }
}