public class MyHttpUrlConnection { 
 private final int mTimeout = 10000; // 超时时间 
 /** 
 * get访问 
 */ 
 public String[] requestJson(String url) { 
 return request(url); 
 } 
 private String[] request(String connurl) { 
 String[] resultStr = new String[]{"", ""}; 
 StringBuilder resultData = new StringBuilder(""); 
 HttpURLConnection conn = null; 
 try { 
  URL url = new URL(connurl); 
  conn = (HttpURLConnection) url.openConnection(); 
  conn.setRequestMethod("GET"); 
  conn.setUseCaches(false); 
  conn.setConnectTimeout(mTimeout); 
  conn.connect(); 
  int resultCode = conn.getResponseCode(); 
  InputStreamReader in; 
  if (resultCode == 200) { 
  in = new InputStreamReader(conn.getInputStream()); 
  BufferedReader buffer = new BufferedReader(in); 
  String inputLine; 
  while ((inputLine = buffer.readLine()) != null) { 
   resultData.append(inputLine); 
   resultData.append("\n"); 
  } 
  buffer.close(); 
  in.close(); 
  } 
  resultStr[0] = resultData.toString(); 
  resultStr[1] = resultCode + ""; 
 } catch (Exception e) { 
  e.printStackTrace(); 
 } finally { 
  if (conn != null) { 
  conn.disconnect(); 
  } 
 } 
 return resultStr; 
 } 
} 

 String url = "https://api.weixin.qq.com/sns/jscode2session""&secret=""&js_code=" 
   + jsCode + "&grant_type=authorization_code"; 
 String res[] = connection.requestJson(url); 
 System.out.println(res[0]); 
 JSONObject object = JSON.parseObject(res[0]); 
 String openId = object.getString("openid"); 
 String session_key = object.getString("session_key");

byte[] encrypData = UtilEngine.decode(encData); 
byte[] ivData = UtilEngine.decode(iv); 
byte[] sessionKey = UtilEngine.decode(session_key); 

public static byte[] decrypt(byte[] key, byte[] iv, byte[] encData) 
 throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, 
 InvalidKeyException, BadPaddingException, IllegalBlockSizeException { 
 AlgorithmParameterSpec ivSpec = new IvParameterSpec(iv); 
 Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); 
 SecretKeySpec keySpec = new SecretKeySpec(key, "AES"); 
 cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec); 
 return cipher.doFinal(encData); 
}