java socket读入未知大小inputstream的客户端

import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.net.Socket;

public class Client {
  public static void main(String[] argv) throws Exception {
    Socket sock = new Socket("127.0.0.1", 9999);
    byte[] mybytearray = new byte[1024];
    InputStream is = sock.getInputStream();
    FileOutputStream fos = new FileOutputStream("test-copy.xml");
    BufferedOutputStream bos = new BufferedOutputStream(fos);
    int data;
    while((data=is.read())!=-1)
    {
    	bos.write(data);
    }
    bos.close();
    sock.close();
  }
}