Java窗口登录代码（附带窗口类转化）

代码说明：

package firstjava; import java.awt.Color; import java.awt.Dimension; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.net.Socket; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPasswordField; import javax.swing.JTextField; public class login  { public static void main(String[] args)  { final String userName = "abc"; final String passwrod = "123"; Socket socket1=null; ObjectInputStream InputStream=null;  ObjectOutputStream OutputStream=null; JFrame jFrame = new JFrame("登陆界面"); Dimension dimension = Toolkit.getDefaultToolkit().getScreenSize(); jFrame