showbook2.java

用java实现图书资料管理系统 操作系统：Windows 数据库：Windows Access 数据库 开发平台：NetBeans 开发语言：Java 语言

/*
 * showbook2.java
 *
 * Created on 2007年12月27日, 上午3:56
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

/**
 *
 * @author Owner
 */

import java.applet.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.ButtonGroup;
import java.sql.*;
import java.util.*;
import java.util.Date;

class test extends Panel {
    Connection con;
    Statement sql;
    ResultSet rs;
    String s;
    int n;
    int a[ ];
    String name[];
    String title="库存图";
    test()
    {
        try
        {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
        }
        catch(ClassNotFoundException e2){}
        try
        {
            con=DriverManager.getConnection("jdbc:odbc:sample","std","123");
            sql=con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
            s="select * from storage";
            rs=sql.executeQuery(s);
            rs.last();
            n=rs.getRow();
            a=new int[n];
            name=new String[n];
            rs.beforeFirst();
            int i=0;
            while(rs.next())
            {
                a[i]=rs.getInt("number");
                name[i]=rs.getString("bookname");
                i++;
            }
        }
        catch(SQLException e)
        {
            System.out.println(e);
        }
    }
    public void paint(Graphics g) {
	g.setFont(new Font(this.getFont().getName(), this.getFont().getStyle(), 30));
	g.drawString(title, 190, 60);
	g.drawLine(30, 30, 30, 320); //画X和Y坐标g.drawLine(30, 320, 470, 320);
	g.setFont(new Font(this.getFont().getName(), this.getFont().getStyle(), 15));
	for(int i=0; i<n; i++) {
		g.setColor(new Color((int)(Math.random()*256),(int)(Math.random()*256),(int)(Math.random()*256)));
		g.fillRect(35+i*40, (320-a[i]*20), 30, a[i]*20);
		g.drawString(name[i], 35+i*40, 340);
	}
    }
}

public class showbook2 extends JFrame
{
	test test;
        userflag userflag;
	showbook2(userflag userflag)
	{
                this.userflag=userflag;
                this.userflag=userflag;
                if(userflag.flag==false)
                {
                    JOptionPane.showMessageDialog(this,"您还没登录");
                    add(new Label("请先登录"),BorderLayout.CENTER);
                }
                else
                {
                    test=new test();
                    add(test);

                    setBounds(100,100,600,400);
                    setVisible(true);
                    validate();
                }
	}
}