Android获取响应头

最近要搞一个安卓项目，于是学了一波安卓的前后端分离，代码参考的菜鸟教程，改进了一下，在页面类中组装好url地址，使PostUtils能够实现复用。

String UpdateAsset_URL = "http://192.168.123.123:8080/updateAsset";//调用的方法接口
        new Thread(){
            public void run() {
                try {
                    //取得参数

                    String data = "";//添加传递的参数
                    result = PostUtils.MainPost(data,UpdateAsset_URL);//获得返回值
                    handler.sendEmptyMessage(0x123);//toast弹窗
                    //添加逻辑部分

                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }.start();

页面代码：

public class LoginActivity extends AppCompatActivity {
    //这里填写个人的主机号
    private final static String LOGIN_URL = "http://192.168.123.123:8080/ServletForPost";
    private String result = "";

    private Handler handler = new Handler() {
        public void handleMessage(android.os.Message msg) {
            Toast.makeText(LoginActivity.this, result, Toast.LENGTH_SHORT).show();
        };
    };
    @BindView(R.id.et_user_name)
    EditText mUsername;

    @BindView(R.id.et_pwd)
    EditText mPassword;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        ButterKnife.bind(this);
    }

    @OnClick(R.id.btn_login)
    public void onViewClicked(){
        new Thread(){
            public void run() {

                String username = mUsername.getText().toString();
                String password = mPassword.getText().toString();

                try {

                    String data = "i="+ URLEncoder.encode(username, "UTF-8")+
                            "&j="+ URLEncoder.encode(password, "UTF-8");
                    result = PostUtils.MainPost(data,LOGIN_URL);
                    handler.sendEmptyMessage(0x123);

                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }.start();
    }
}

PostUtils：

public class PostUtils {
        public static String MainPost(String data,String url)
        {
            String msg = "1";
            try{
                HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();
                //设置请求方式,请求超时信息
                conn.setRequestMethod("POST");
                conn.setReadTimeout(5000);
                conn.setConnectTimeout(5000);
                //设置运行输入,输出:
                conn.setDoOutput(true);
                conn.setDoInput(true);
                //Post方式不能缓存,需手动设置为false
                conn.setUseCaches(false);
                //获取输出流
                OutputStream out = conn.getOutputStream();
                out.write(data.getBytes());
                out.flush();
                if (conn.getResponseCode() == 200) {
                    // 获取响应的输入流对象
                    InputStream is = conn.getInputStream();
                    // 创建字节输出流对象
                    ByteArrayOutputStream message = new ByteArrayOutputStream();
                    // 定义读取的长度
                    int len = 0;
                    // 定义缓冲区
                    byte buffer[] = new byte[1024];
                    // 按照缓冲区的大小，循环读取
                    while ((len = is.read(buffer)) != -1) {
                        // 根据读取的长度写入到os对象中
                        message.write(buffer, 0, len);
                    }
                    // 释放资源
                    is.close();
                    message.close();
                    // 返回字符串
                    msg = new String(message.toByteArray());
                    return msg;
                }
            }catch(Exception e){e.printStackTrace();}
            return msg;
        }
    }