关于snsapi_base网页授权的说明
以snsapi_base为scope发起的网页授权，是用来获取进入页面的用户的openid的，并且是静默授权并自动跳转到回调页的。用户感知的就是直接进入了回调页（往往是业务页面）
微信打开链接（https://open.weixin.qq.com/connect/oauth2/authorize?appid=wx48414ee14f7d7158
&redirect_uri=http://test.cn/testWx//servlet/Oauth2Servlet&response_type=code&scope=snsapi_base&state=1&connect_redirect=1#wechat_redirect）
即可看到效果，效果截图如下:
只打印了 openid。
具体代码如下：（代码参考博客：http://www.cnblogs.com/zyw-205520/p/3581088.html）
Oauth2Servlet.java
package com.payroll.wx.servlet; import java.io.IOException; import java.io.PrintWriter; 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 com.payroll.wx.util.CommendDef; import com.payroll.wx.util.HttpsGetUtil; public class CopyOfOauth2Servlet extends HttpServlet { /** * */ private static final long serialVersionUID = 1L; /** * The doGet method of the servlet. <br> * * This method is called when a form has its tag value method equals to get. * * @param request * the request send by the client to the server * @param response * the response send by the server to the client * @throws ServletException * if an error occurred * @throws IOException * if an error occurred */ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //静默授权 String get_access_token_url = "https://api.weixin.qq.com/sns/oauth2/access_token?" + "appid=" + CommendDef.AppId + "&secret=" + CommendDef.AppSecret + "&code=CODE&grant_type=authorization_code"; // 将请求、响应的编码均设置为UTF-8（防止中文乱码） request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); String code = request.getParameter("code"); System.out.println("******************code=" + code); get_access_token_url = get_access_token_url.replace("CODE", code); String json = HttpsGetUtil.doHttpsGetJson(get_access_token_url); JSONObject jsonObject = JSONObject.fromObject(json); String openid = jsonObject.getString("openid"); response.setContentType("text/html; charset=utf-8"); PrintWriter out = response.getWriter(); out.println("<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">"); out.println("<HTML>"); out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>"); out.println(" <BODY>"); out.print(" This is "); out.print(this.getClass()); out.println(", using the POST method "); out.println("openid:" + openid + " "); out.println(">"); out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close(); } }
HttpsGetUtil.java
package com.payroll.wx.util; import java.io.IOException; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; public class HttpsGetUtil { public static String doHttpsGetJson(String Url) { String message = ""; try { System.out.println("doHttpsGetJson");//TODO:dd URL urlGet = new URL(Url); HttpURLConnection http = (HttpURLConnection) urlGet.openConnection(); http.setRequestMethod("GET"); //必须是get方式请求 24 http.setRequestProperty("Content-Type","application/x-www-form-urlencoded"); http.setDoOutput(true); http.setDoInput(true); System.setProperty("sun.net.client.defaultConnectTimeout", "30000");//连接超时30秒28 System.setProperty("sun.net.client.defaultReadTimeout", "30000"); //读取超时30秒29 30 http.connect(); InputStream is =http.getInputStream(); int size =is.available(); byte[] jsonBytes =new byte[size]; is.read(jsonBytes); message=new String(jsonBytes,"UTF-8"); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return message; } }