基于注解的实现获取微信openId1

最近在弄微信支付，网站有好几种不同类型的"商品"，去每个支付的页面都需要获取用户的OpenId，而且获取openid要在微信的浏览器去发送请求，如果有三个不同类型的付款页面就需要写三个一样获取openid的方法，这为了以后如果网站需要在其他的地方获取openid，为了扩展所以lz想了一个办法 把获取微信openId的方法抽取成了用注解和spring mvc的拦截器来实现。废话不多说下面直接上代码。

1.获取微信openid 网页授权代码

这里就不详细说啦，可以参照点击打开链接微信开发文档，下面也会体现到网页授权

注解代码实现

package com.workit.handler;import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/**
*
* @Title: WeiXinGetOpenId.java
* @Description: 获取openId注解，needGetOpenId 为true时调用获取openid
* @date 2017年5月9日 下午4:12:02
* @version V1.0
*/
@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface WeiXinGetOpenId { /**
*
* @Title: needGetOpenId
* @Description: 是否需要获取OpenId。
* @param @return
* @return boolean
*/
boolean needGetOpenId() default false; /**
*
* @Title: needGetUserInfo
* @Description: 是否需要获取用户信息。
* @param @return
* @return boolean
*/
boolean needGetUserInfo() default false; /**
*
* @Title: scopeType
* @Description: 授权方式
* @param @return
* @return String
*/
String scopeType() default "snsapi_base";}


spring mvc配置文件加入下代码

<mvc:interceptors>
<!-- 获取OpenId注解 -->
<mvc:interceptor>
<!-- <mvc:mapping path="/**"/>这个地方时你要拦截得路径 我这个意思是拦截所有得URL -->
<mvc:mapping path="/**/*"/>
<mvc:exclude-mapping path="/**/fonts/*"/>
<mvc:exclude-mapping path="/**/*.css"/>
<mvc:exclude-mapping path="/**/*.js"/>
<mvc:exclude-mapping path="/**/*.png"/>
<mvc:exclude-mapping path="/**/*.gif"/>
<mvc:exclude-mapping path="/**/*.jpg"/>
<mvc:exclude-mapping path="/**/*.jpeg"/>
<bean class="com.jkinvest.sme.web.handler.WeixinGetOpenIdHandlerInterceptor"/><!--class文件路径改成你自己写得拦截器路径！！ -->
</mvc:interceptor>
</mvc:interceptors>

拦截器代码实现类

package com.workit.handler;import java.net.URLEncoder;
import java.util.Enumeration;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import com.alibaba.fastjson.JSONObject;
import com.workit.comm.util.GlobalConstant;
import com.workit.comm.util.String.StringUtil;
import com.workit.comm.util.weixin.WeiXinConstant;
import com.workit.comm.util.weixin.WeiXinUtil;/**
* @Title: WeixinGetOpenIdHandlerInterceptor.java
* @Description: TODO
* @date 2017年5月9日 上午10:56:45
* @version V1.0
*/
public class WeixinGetOpenIdHandlerInterceptor implements HandlerInterceptor {@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
if (handler instanceof HandlerMethod) {
HandlerMethod method = (HandlerMethod) handler;
WeiXinGetOpenId annotation = method.getMethodAnnotation(WeiXinGetOpenId.class);
if(WeiXinUtil.checkWeiXinAgent(request)){
if (annotation != null) {
boolean needGetOpenId = annotation.needGetOpenId();
String scopeType= annotation.scopeType();
if (needGetOpenId) {
String url =request.getRequestURI();
String methodType = request.getMethod();
@SuppressWarnings("rawtypes")
Enumeration enu=request.getParameterNames();
JSONObject json = new JSONObject();
json.put("targetUrl",url);
json.put("submitMethodType",methodType);
while(enu.hasMoreElements()){
String paraName=(String)enu.nextElement();
json.put(paraName, request.getParameter(paraName));
}
//说明已经获取过OpenId
if(StringUtil.isNotEmpty(json.get("weiXinGetOpenIdFlag"))){
return true;
}else{
String jsonParams = json.toJSONString();
String returnUrl ="网站名字"+"/WeiXinCommGetOpenId.html?weixin_outh2_params="+jsonParams;
returnUrl=URLEncoder.encode(returnUrl,"UTF-8");
String scope =scopeType;
returnUrl = WeiXinConstant.WEIXIN_AUTH_URL.replace("APPID",GlobalConstant.SERVICE_APPID).replace("REDIRECT_URI", returnUrl).replace("SCOPE", scope);
response.sendRedirect(returnUrl);
return false;
}
}
}
}
}
return true;
}@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
// TODO Auto-generated method stub}@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
throws Exception {
// TODO Auto-generated method stub}}


获取OpenId的类

package com.workit.handler;import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;import com.workit.comm.util.weixin.WeiXinUtil;/**
* @Title: WeiXinCommGetOpenId.java
* @Description: TODO
* @date 2017年5月9日 下午1:45:30
* @version V1.0
*/
@Controller
public class WeiXinCommGetOpenId {
private static final Logger logger = LoggerFactory.getLogger(WeiXinCommGetOpenId.class);@RequestMapping("/WeiXinCommGetOpenId.html")
public void getWeiXinCommOpenId(HttpServletRequest request,HttpServletResponse response) throws IOException{
Map<String,Object> paramMap = new HashMap<String,Object>();
String postUrl ="";
try {
String code = request.getParameter("code");
String weixin_outh2_params = request.getParameter("weixin_outh2_params");
JSONObject json = new JSONObject(weixin_outh2_params);
String clickOpenId = WeiXinUtil.getUserInfoOpenId(code);
Iterator<?> it = json.keys();
postUrl = json.getString("targetUrl");
if(postUrl.contains("网站名字")){
postUrl = postUrl.replace("网站名字/","");
}
postUrl ="网站名字"+postUrl;
paramMap.put("weiXinOpenId", clickOpenId);
paramMap.put("weiXinGetOpenIdFlag","isTure");
while (it.hasNext()) {
String key = (String) it.next();
String value = json.getString(key);
paramMap.put(key, value);
}
} finally {
// TODO: handle finally clause
doReq(response, postUrl, paramMap);
}}
/**
*
* @param response
* @param postUrl
* @param paramMap
* @throws IOException
*/
public static void doReq(HttpServletResponse response,String postUrl,Map<String, ?> paramMap) throws IOException {
logger.debug("go into doReq method");
response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
String type =(String) paramMap.get("submitMethodType");
out.println("<form name='postSubmit' method='"+type+"' target='_blank' action='"+postUrl+"' >");
for (String key : paramMap.keySet()) {
out.println("<input type='hidden' name='"+key+"' value='" + paramMap.get(key)+ "'>");
}
out.println("</form>");
out.println("<script>");
out.println("document.postSubmit.submit()");
out.println("</script>");
logger.debug("======doReq =====");
}
}


使用只要在获取需要获取OPenID的方法前面加上注解

@WeiXinGetOpenId(needGetOpenId=true)

在方法里通过request.getParams("weiXinOpenId")