public static AccessToken getAccessToken(String appid, String appsecret) {  
	    AccessToken accessToken = null;  
	    String requestUrl = access_token_url.replace("APPID", appid).replace("APPSECRET", appsecret);  
	    JSONObject jsonObject = httpRequest(requestUrl, "GET", null);  
	    // 如果请求成功  
	    if (null != jsonObject) {  
	        try {  
	            accessToken = new AccessToken();  
	            accessToken.setToken(jsonObject.getString("access_token"));  
	            accessToken.setExpiresIn(jsonObject.getInt("expires_in"));  
	        } catch (JSONException e) {  
	            accessToken = null;  
	            // 获取token失败  
	            log.error("获取token失败 errcode:{"+jsonObject.getInt("errcode") +"} errmsg:{"+jsonObject.getString("errmsg")+"}");
	        }  
	    }  
	    return accessToken;  
	}