java 微信小程序code获取openid的操作

import com.alibaba.fastjson.JSON;

import com.alibaba.fastjson.JSONObject;

import com.moszk.frame.basic.utils.HttpRequest;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.ResponseBody;

import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;

import java.util.Map;

@RestController

public class WeiXinSubmitController {

     @ResponseBody

     @RequestMapping (value = "/wx/decodeUserInfo" , method = RequestMethod.GET)

     public Map decodeUserInfo(String code) {

         System.out.println(code);

         Map map = new HashMap();

         //登录凭证不能为空

         if (code == null || code.length() == 0 ) {

             map.put( "status" , 0 );

             map.put( "msg" , "code 不能为空" );

             return map;

         }

         //小程序唯一标识   (在微信小程序管理后台获取)

         String wxspAppid = "***********" ;

         //小程序的 app secret (在微信小程序管理后台获取)

         String wxspSecret = "*********************" ;

         //授权（必填）

         String grant_type = "authorization_code" ;

         //https://api.weixin.qq测试数据/sns/jscode2session?appid=APPID&secret=SECRET&js_code=JSCODE&grant_type=authorization_code

         //1、向微信服务器 使用登录凭证 code 获取 session_key 和 openid

         //请求参数

         String params = "appid=" + wxspAppid + "&secret=" + wxspSecret + "&js_code=" + code + "&grant_type=" + grant_type;

         //发送请求

         String sr = HttpRequest.sendGet( "https://api.weixin.qq测试数据/sns/jscode2session" , params);

         System.out.println( "sr========" +sr);

         //解析相应内容（转换成json对象）

         JSONObject json =JSON.parseObject(sr);

         System.out.println( "json============" +json);

         //获取会话密钥（session_key）json.get("session_key").toString();

         String session_key = json.get( "session_key" ).toString();

         //用户的唯一标识（openid）

         String openid = (String) json.get( "openid" );

         map.put( "session_key" ,session_key);

         map.put( "openid" ,openid);

         return map;

     }

}

import java.io.*;

import java.net.URL;

import java.net.URLConnection;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.text.SimpleDateFormat;

import java.util.*;

public class HttpRequest {

     /**

      * 向指定URL发送GET方法的请求

      *

      * @param url

      *            发送请求的URL

      * @param param

      *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。

      * @return URL 所代表远程资源的响应结果

      */

     public static String sendGet(String url, String param) {

         String result = "" ;

         BufferedReader in = null ;

         try {

             String urlNameString = url + "?" + param;

             URL realUrl = new URL(urlNameString);

             // 打开和URL之间的连接

             URLConnection connection = realUrl.openConnection();

             // 设置通用的请求属性

             connection.setRequestProperty( "accept" , "*/*" );

             connection.setRequestProperty( "connection" , "Keep-Alive" );

             connection.setRequestProperty( "user-agent" ,

                     "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)" );

             // 建立实际的连接

             connection.connect();

             // 获取所有响应头字段

             Map<String, List<String>> map = connection.getHeaderFields();

             // 遍历所有的响应头字段

             for (String key : map.keySet()) {

                 System.out.println(key + "--->" + map.get(key));

             }

             // 定义 BufferedReader输入流来读取URL的响应

             in = new BufferedReader( new InputStreamReader(

                     connection.getInputStream()));

             String line;

             while ((line = in.readLine()) != null ) {

                 result += line;

             }

         } catch (Exception e) {

             System.out.println( "发送GET请求出现异常！" + e);

             e.printStackTrace();

         }

         // 使用finally块来关闭输入流

         finally {

             try {

                 if (in != null ) {

                     in.close();

                 }

             } catch (Exception e2) {

                 e2.printStackTrace();

             }

         }

         return result;

     }

     /**

      * 向指定 URL 发送POST方法的请求

      *

      * @param url

      *            发送请求的 URL

      * @param param

      *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。

      * @return 所代表远程资源的响应结果

      */

     public static String sendPost(String url, String param, String keyValue) {

         PrintWriter out = null ;

         BufferedReader in = null ;

         String result = "" ;

         try {

             URL realUrl = new URL(url);

             // 打开和URL之间的连接

             URLConnection conn = realUrl.openConnection();

             // 设置通用的请求属性

             conn.setRequestProperty( "accept" , "*/*" );

             conn.setRequestProperty( "connection" , "Keep-Alive" );

             conn.setRequestProperty( "api-key" , keyValue); 

             conn.setRequestProperty( "user-agent" ,

                     "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)" );

             conn.setRequestProperty( "Accept-Charset" , "UTF-8" );

             // 发送POST请求必须设置如下两行

             conn.setDoOutput( true );

             conn.setDoInput( true );

             // 获取URLConnection对象对应的输出流

             //out = new PrintWriter(conn.getOutputStream());

             out = new PrintWriter( new OutputStreamWriter(conn.getOutputStream(), "UTF-8" ));

             // 发送请求参数

             out.print(param);

             // flush输出流的缓冲

             out.flush();

             // 定义BufferedReader输入流来读取URL的响应

             in = new BufferedReader(

                       new InputStreamReader(conn.getInputStream(), "UTF-8" ));

             String line;

             while ((line = in.readLine()) != null ) {

                 System.out.println(line);

                 result += line;

             }

         } catch (Exception e) {

             System.out.println( "发送 POST 请求出现异常！" +e);

             e.printStackTrace();

         }

         //使用finally块来关闭输出流、输入流

         finally {

             try {

                 if (out!= null ){

                     out.close();

                 }

                 if (in!= null ){

                     in.close();

                 }

             }

             catch (IOException ex){

                 ex.printStackTrace();

             }

         }

         return result;

     }

     public static String generateOrderId(){

         String keyup_prefix= new SimpleDateFormat( "yyyyMMddHHmmss" ).format( new Date());

         String keyup_append= String.valueOf( new Random().nextInt( 899999 )+ 100000 );

         String pay_orderid=keyup_prefix+keyup_append; //订单号

         return pay_orderid;

     }

     public static String generateTime(){

         return new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" ).format( new Date());

     }

     public static String md5(String str) throws NoSuchElementException {

         try {

             MessageDigest md = MessageDigest.getInstance( "MD5" );

             md.update(str.getBytes( "UTF-8" ));

             byte [] byteDigest = md.digest();

             int i;

             //字符数组转换成字符串

             StringBuffer buf = new StringBuffer( "" );

             for ( int offset = 0 ; offset < byteDigest.length; offset++) {

                 i = byteDigest[offset];

                 if (i < 0 )

                     i += 256 ;

                 if (i < 16 )

                     buf.append( "0" );

                 buf.append(Integer.toHexString(i));

             }

             // 32位加密

             return buf.toString(); //toUpperCase

             // 16位的加密

              //return buf.toString().substring(8, 24).toUpperCase();

         } catch (NoSuchAlgorithmException | UnsupportedEncodingException e) {

             e.printStackTrace();

             return null ;

         }

     }

}