用java向一个WEB发送psot请求

Question

怎么才是连接成功 ，用不用在获得输入前加setdoinput(true)。
import java.net.*;
import java.io.*;
public class Test
{
public Test()
{
try
{
URL url = new URL("http://www.xiaonei.com/Login.do");
URLConnection connection = url.openConnection();
        connection.setDoOutput(true);
        OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(),"8859_1");
        out.write("email=帐号&password=密码");
        out.flush();
        out.close();
        //connection.setDoInput(true);
        InputStreamReader read=new InputStreamReader(connection.getInputStream());
        BufferedReader reader=new BufferedReader(read);
        StringBuffer str =new StringBuffer();
        System.out.println("ok");
        while((reader.readLine())!=null)
        {
         str.append(reader);
        }
        System.out.println(str);
        }catch(Exception e) 
        {
        System.out.println("mistake");
        }  
}
public static void main(String[] args) 
{
Test aa=new Test();
}
}