利用JDBC获取数据库的记录

1、新建一个ACCESS数据库，新建一个表BookData，表结构如下：

-------------------------------------------------

字段名称      数据类型      字段大小

ISBN                  文字            13

BookName          文字            50

Author               文字            30

Price                   数字            长整数     

--------------------------------------------------

2、在ODBC的用户DSN中新建一个数据源"myBook"。

3、源代码如下：

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;

/**
 *
 * @author Administrator
 */
public class MyBook extends JFrame{
    Connection ConnObj;
    Statement SQLStatement;
    ResultSet RS;
    //========================================
    JPanel contentPanel;
    Panel panel1;
    Label L1,L2,L3,L4;
    TextField T1,T2,T3,T4;
    Button B1,B2,B3,B4;

    public MyBook() {
        contentPanel=(JPanel)this.getContentPane();
        contentPanel.setLayout(null);
        //=============================================
        panel1=new Panel();
        panel1.setBounds(0, 0, 290, 130);
        panel1.setLayout(null);
        panel1.setEnabled(false);

        contentPanel.add(panel1);//panel1是加在contentPane内
        //用来显示一条数据的组件是加在panel1内
        L1=new Label("ISBN:");
        L1.setBounds(20, 10, 50, 25);
        panel1.add(L1);
        L2=new Label("书名：");
        L2.setBounds(20, 40, 50, 25);
        panel1.add(L2);
        L3=new Label("作者：");
        L3.setBounds(20, 70, 50, 25);
        panel1.add(L3);
        L4=new Label("价格：");
        L4.setBounds(20, 100, 50, 25);
        panel1.add(L4);
        T1=new TextField();
        T1.setBounds(70, 10, 200, 25);
        panel1.add(T1);
        T2=new TextField();
        T2.setBounds(70, 40, 200, 25);
        panel1.add(T2);
        T3=new TextField();
        T3.setBounds(70, 70, 200, 25);
        panel1.add(T3);
        T4=new TextField();
        T4.setBounds(70, 100, 200, 25);
        panel1.add(T4);
        //==========================================
        B1=new Button("第一条");
        B1.setBounds(new Rectangle(10, 150, 65, 20));
        B1.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mouseClicked(final MouseEvent e) {
                B1_mouseClicked(e);//程序代码较多，写在另一个方法中
            }
        });
        contentPanel.add(B1);

        B2=new Button("上一条");
        B2.setBounds(new Rectangle(80, 150, 65, 20));
        B2.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mouseClicked(final MouseEvent e) {
                B2_mouseClicked(e);//程序代码较多，写在另一个方法中
            }
        });
        contentPanel.add(B2);

        B3=new Button("下一条");
        B3.setBounds(new Rectangle(150, 150, 65, 20));
        B3.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mouseClicked(final MouseEvent e) {
                B3_mouseClicked(e);//程序代码较多，写在另一个方法中
            }
        });
        contentPanel.add(B3);

        B4=new Button("最末条");
        B4.setBounds(new Rectangle(220, 150, 65, 20));
        B4.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mouseClicked(final MouseEvent e) {
                B4_mouseClicked(e);//程序代码较多，写在另一个方法中
            }
        });
        contentPanel.add(B4);
        //=========================================================
        this.setBounds(200, 100, 310, 210);
        this.setTitle("使用 Select 语句");
        //this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.addWindowListener(new WindowAdapter()
        {
            @Override
            public void windowClosing(final WindowEvent e) {
                System.exit(0);
            }
        });
        this.setVisible(true);
        //=========================================================
        //加载JDBC Driver、连接数据库、送SELECT语句、返回结果集
        try
        {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            //载入JDBC Driver
            ConnObj=DriverManager.getConnection("jdbc:odbc:myBook");
            //连接ODBC设置的myBook数据源，jdbc:subprotocol:Alias
            SQLStatement=ConnObj.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
            //其后由此Statement对象执行SQL指令时，返回的会是可卷动且只读的ResultSet对象
            RS=SQLStatement.executeQuery("select * from BookData");
            //执行SELECT语句，会返回一个结果集
            //查询myBook数据源的BookData数据表全部字段的记录
            
            //必须先向下移到第一条：next(),因为一开始是指到第一条之前
            if(RS.next())
            {
                //RS内至少有一条记录，才会返回true
                T1.setText(RS.getString("ISBN"));
                T2.setText(RS.getString("BookName"));
                T3.setText(RS.getString("Author"));
                T4.setText(String.valueOf(RS.getInt("Price")));
            }
            else
                JOptionPane.showMessageDialog(this, "myBook数据库内，无任何数据");
        }
        catch(Exception ex)
        {
            JOptionPane.showMessageDialog(this, ex.getMessage());
        }
        
    }

    void B1_mouseClicked(final MouseEvent e)
    {
        try
        {
            RS.first();
            T1.setText(RS.getString("ISBN"));
            T2.setText(RS.getString("BookName"));
            T3.setText(RS.getString("Author"));
            T4.setText(String.valueOf(RS.getInt("Price")));
        }
        catch(SQLException ex){}
    }

    void B2_mouseClicked(final MouseEvent e)
    {
        try
        {
            if(RS.previous())
            {
                T1.setText(RS.getString("ISBN"));
                T2.setText(RS.getString("BookName"));
                T3.setText(RS.getString("Author"));
                T4.setText(String.valueOf(RS.getInt("Price")));
            }
            else
            {
                RS.first();
                JOptionPane.showMessageDialog(B2,"已到第一条");
            }
        }
        catch(SQLException ex){}
    }
    
    void B3_mouseClicked(final MouseEvent e)
    {
        try
        {
            if(RS.next())
            {
                T1.setText(RS.getString("ISBN"));
                T2.setText(RS.getString("BookName"));
                T3.setText(RS.getString("Author"));
                T4.setText(String.valueOf(RS.getInt("Price")));
            }
            else
            {
                RS.last();
                JOptionPane.showMessageDialog(B3, "已到最末条");
            }
        }
        catch(SQLException ex){}
    }
    
    void B4_mouseClicked(final MouseEvent e)
    {
        try
        {
            RS.last();
            T1.setText(RS.getString("ISBN"));
            T2.setText(RS.getString("BookName"));
            T3.setText(RS.getString("Author"));
            T4.setText(String.valueOf(RS.getInt("Price")));
        }
        catch(SQLException ex){}
    }
    /**
     * @param args the command line arguments
     */
    public static void main(final String[] args) {
        // TODO code application logic here
        new MyBook();
    }

}