java微信接口之——获取access_token

 1 package com.demo.test;
 2 
 3 import org.apache.http.HttpEntity;
 4 import org.apache.http.HttpResponse;
 5 import org.apache.http.HttpStatus;
 6 import org.apache.http.client.HttpClient;
 7 import org.apache.http.client.methods.HttpGet;
 8 import org.apache.http.impl.client.DefaultHttpClient;
 9 import org.apache.http.util.EntityUtils;
10 
11 import com.google.gson.JsonObject;
12 import com.google.gson.JsonParser;
13 
14 public class Test
15 {
16     public static final String GET_TOKEN_URL = "https://api.weixin.qq.com/cgi-bin/token";// 获取access
17                                                                                             // url
18     public static final String APP_ID = "wxa549b28c24cf341e";
19     public static final String SECRET = "78d8a8cd7a4fa700142d06b96bf44a37";
20 
21     // 获取token
22     public static String getToken(String apiurl, String appid, String secret)
23     {
24         String turl = String.format(
25                 "%s?grant_type=client_credential&appid=%s&secret=%s", apiurl,
26                 appid, secret);
27         HttpClient client = new DefaultHttpClient();
28         HttpGet get = new HttpGet(turl);
29         JsonParser jsonparer = new JsonParser();// 初始化解析json格式的对象
30         String result = null;
31         try
32         {
33             HttpResponse res = client.execute(get);
34             String responseContent = null; // 响应内容
35             HttpEntity entity = res.getEntity();
36             responseContent = EntityUtils.toString(entity, "UTF-8");
37             JsonObject json = jsonparer.parse(responseContent)
38                     .getAsJsonObject();
39             // 将json字符串转换为json对象
40             if (res.getStatusLine().getStatusCode() == HttpStatus.SC_OK)
41             {
42                 if (json.get("errcode") != null)
43                 {// 错误时微信会返回错误码等信息，{"errcode":40013,"errmsg":"invalid appid"}
44                 }
45                 else
46                 {// 正常情况下{"access_token":"ACCESS_TOKEN","expires_in":7200}
47                     result = json.get("access_token").getAsString();
48                 }
49             }
50         }
51         catch (Exception e)
52         {
53             e.printStackTrace();
54         }
55         finally
56         {
57             // 关闭连接 ,释放资源
58             client.getConnectionManager().shutdown();
59             return result;
60         }
61     }
62 
63     public static void main(String[] args) throws Exception
64     {
65         System.out.println("=========1获取token=========");
66         String accessToken = getToken(GET_TOKEN_URL, APP_ID, SECRET);// 获取token
67         if (accessToken != null)
68             System.out.println(accessToken);
69     }
70 
71 }