请教高手关于Servlet问题

这是一个
package com.android.service;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class LoginServlet extends HttpServlet
{
    public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException
    {

        Connection conn;
        PreparedStatement sql;
        ResultSet rs;


        String username = request.getParameter("username");
        String password = request.getParameter("password");
        response.setContentType("text/html");
        response.setCharacterEncoding("utf-8");
        PrintWriter out = response.getWriter();
        String result = null;


            if(username!=null&&password!=null)
            {

                if(password.equals("123"))
                {
                    result = "success";
                }else
                {
                    result = "failed";
                }
            }else
            {
                result = "failed";
            }

        out.print(result);

    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException,IOException
    {
        doGet(request, response);
    }

}

调用上面的。
private void loginServer(String username, String password){
     //boolean loginValidate = false;
     String urlStr = "http://127.0.0.1:8080/android/LoginServlet";
     String queryString = "?username="+username+"&password="+password;
     urlStr = urlStr+queryString;
     try{
     //实例化url
URL url = new URL(urlStr);
//获得HttpURLConnection实例
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
int code = conn.getResponseCode();
if(code==200){//如果请求成功
//获得输入流
InputStream is = conn.getInputStream();
byte[] b = new byte[is.available()];
is.read(b);
//转化字符串
String result = new String(b);
Toast.makeText(this, result, 1000).show();
}
}
catch (MalformedURLException e) {
     e.printStackTrace();
     }catch(IOException e){
     e.printStackTrace();}}
为什么我加断点后，走到IF 就直接跳过去了，然后我该如何把out.print(result);这个的值取过来。

补充：移动开发 ,  Android