myeclipse无法进行图形界面编程
运行图形界面程序，没有反应。。程序应该没有什么问题

Java code

package com.test1;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JScrollBar;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.JTextField;public class MyServer3 extends JFrame{    JTextArea jta=null;    JTextField jtf=null;    JButton jb=null;    JScrollPane jsp=null;        JPanel jp1=null;        /**     * @param args     */    public static void main(String[] args) {        // TODO Auto-generated method stub    }    public MyServer3(){        jta=new JTextArea();        jsp=new JScrollPane(jta);        jtf=new JTextField(20);        jb=new JButton("发送");        jp1=new JPanel();        jp1.add(jtf);        jp1.add(jb);                this.add(jsp,"Center");        this.add(jp1,"South");        this.setSize(400,300);        this.setVisible(true);            }}