java微信开发获取access_token

获取微信接口

@RequestMapping("wx")
@Controller
public class WxController extends BaseController {
    String access_token = null;
    private static final String appid = "xxx";
    private static final String secret = "xxx";
    private static final String grant_type = "client_credential";   

    /**
     * 微信获取token
     * @param request
     * @return
     */
    @RequestMapping(value="/getToken",method=RequestMethod.GET)
    @ResponseBody
    public String getToken(HttpServletRequest request){
//      Map map = new HashMap();
        String status="";
        try {
            access_token = HttpRequest.sendGet("https://api.weixin.qq.com/cgi-bin/token",
                    "grant_type=" + grant_type + "&appid=" + appid + "&secret=" + secret + "");
        } catch (Exception e) {
            e.printStackTrace();
            status = "wrong";
            return status;
        }
        return access_token;
    }

}

http请求实现

public class HttpRequest {
    /**
     * access_token获取
     * @author xx
     *
     */
    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> 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;
    }

}