java hibernate问题

这是完整的程序自己去看吧
package com.huabo;

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Panel;
import java.awt.TextField;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class Computer extends Frame{
    
     
	 public Computer(){
		 super("计算器");
		 
		 //给窗口布局
		 BorderLayout borderlayout_frame = new BorderLayout();
		 this.setLayout(borderlayout_frame);
		 
		 // 将窗口分成上下两部分
		 
		 Panel panel_north = new Panel();
		 GridLayout panel_north1 = new GridLayout(2,1);
		 //panel_north(panel_north);
		 
		 TextField textfield_top = new TextField("0.",30);
		 textfield_top.setBackground(Color.lightGray);
		 panel_north.add(textfield_top);
		 Panel pancel_center = new Panel();
		 this.add(panel_north ,BorderLayout.NORTH);
		 this.add(pancel_center,BorderLayout.CENTER);
		 
		 //将第二部分成三部分
		 BorderLayout borderlayout_center = new BorderLayout();
		 pancel_center.setLayout(borderlayout_center);
		 Panel panelcenter_north = new Panel();
		 Panel panelcenter_west = new Panel();
		 Panel panelcenter_center = new Panel();
		 pancel_center.add(panelcenter_north,BorderLayout.NORTH);
		 pancel_center.add(panelcenter_west,BorderLayout.WEST);
		 pancel_center.add(panelcenter_center,BorderLayout.CENTER);