MyFrame(String s) { 
this.setTitle(s);
this.setLayout(new BorderLayout());
this.setBounds(500, 100, 300, 455);


JPanel p1 = new JPanel(new FlowLayout());
JPanel p3 = new JPanel(new GridLayout(3,1));

JLabel lb = new JLabel("索引 :");
lb.setFont(new Font("黑体",Font.BOLD ,15));

tf = new JTextField(18);

p1.add(lb);
p1.add(tf);
this.add(p1,BorderLayout.NORTH);

this.initialize();
ta = new JTable(model);
ta.setRowSelectionInterval(0, 0);

DefaultTableCellRenderer r = new DefaultTableCellRenderer();
r.setHorizontalAlignment(JLabel.CENTER);
ta.setDefaultRenderer(Object.class, r);
ta.setAutoCreateRowSorter(true);
ta.setBackground(Color.PINK);
sp = new JScrollPane();
sp.getViewport().add(ta);
this.add(sp,BorderLayout.CENTER);

JButton b1 = new JButton("增 加");
b1.setFont(new Font("华文行楷",Font.PLAIN,20));
JButton b2 = new JButton("删 除");
b2.setFont(new Font("华文行楷",Font.PLAIN,20));
JButton b3 = new JButton("修 改");
b3.setFont(new Font("华文行楷",Font.PLAIN,20));
p3.add(b1);
p3.add(b2);
p3.add(b3);
this.add(p3,BorderLayout.SOUTH);

b1.addMouseListener(new MouseListener());
b2.addMouseListener(new MouseListener2());
b3.addMouseListener(new MouseListener3());

this.addWindowListener(new windowMonitor());
ThreadMonitor t = new ThreadMonitor();
t.run();

this.setIconImage(img);
this.validate();
this.setVisible(true);
}

------解决方案--------------------
this.setVisible(true);

放构造方法最后一句试试