multipagequeryframe.java

java 数据库编程源代码

package multipagequery;

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

/**
 * Title:			使用多窗口查询数据库
 * Description:			教学示范
 * Copyright:			Copyright (c) 2003
 * Company:			北京师范大学计算机系
 * @author			孙一林
 * @version			1.0
 */


public class MultiPageQueryFrame extends JFrame {
  private JPanel contentPane;
  private Button displayButton = new Button();
  private Choice tableChoice = new Choice();
  private Button getTableButton = new Button();

  Connection connection = null;                //定义与数据库进行连接的Connection对象
  ResultSet rs = null;                         //定义数据库查询的结果集

  public MultiPageQueryFrame() {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }

  private void jbInit() throws Exception  {          //初始化用户界面
    contentPane = (JPanel) this.getContentPane();
    displayButton.setEnabled(false);
    displayButton.setLabel("显示表中的数据");
    displayButton.setBounds(new Rectangle(231, 212, 135, 38));
    displayButton.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        displayButton_actionPerformed(e);
      }
    });
    contentPane.setLayout(null);
    this.setSize(new Dimension(400, 300));
    this.setTitle("多窗口显示数据库数据");
    tableChoice.setBounds(new Rectangle(93, 64, 204, 36));
    getTableButton.setLabel("取得数据库中的表的名称");
    getTableButton.setBounds(new Rectangle(26, 213, 175, 38));
    getTableButton.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        getTableButton_actionPerformed(e);
      }
    });
    contentPane.add(tableChoice, null);
    contentPane.add(getTableButton, null);
    contentPane.add(displayButton, null);
  }

  protected void processWindowEvent(WindowEvent e) {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      System.exit(0);
    }
  }

  void getTableButton_actionPerformed(ActionEvent e) {   //查询数据库中表的名称并显示
    try
    {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");   //指定与数据库连接使用JDBC-ODBC桥驱动程序
      String url = "jdbc:odbc:student";                //指定数据源名
      connection = DriverManager.getConnection(url);   //与数据源建立连接
      DatabaseMetaData dbData = connection.getMetaData();  //获取数据库的信息
      String[] type = {"TABLE"};                           //指定所需信息为用户表信息
      rs = dbData.getTables(null, null, "%", type);        //获得数据库中所有用户表的信息
      while(rs.next())
      {
        tableChoice.addItem(rs.getString(3));              //获得数据库中所有用户表名
      }
      displayButton.setEnabled(true);
      getTableButton.setEnabled(false);
    }
    catch(SQLException ex){                          //捕捉异常
      System.out.println("\nERROR:----- SQLException -----\n");
      while (ex != null) {
        System.out.println("Message:   " + ex.getMessage());
        System.out.println("SQLState:  " + ex.getSQLState());
        System.out.println("ErrorCode: " + ex.getErrorCode());
        ex = ex.getNextException();
      }
    }
    catch(Exception ex ) {
      ex.printStackTrace();
    }
    finally {
      try {
        if(connection != null)
        {
          connection.close();                   //关闭Connection接口实例
        }
      }
      catch (SQLException ex)  {
        System.out.println("\nERROR:----- SQLException -----\n");
        System.out.println("Message:   " + ex.getMessage());
        System.out.println("SQLState:  " + ex.getSQLState());
        System.out.println("ErrorCode: " + ex.getErrorCode());
      }
    }
  }

  void displayButton_actionPerformed(ActionEvent e) {  //产生新的窗口显示数据库数据
    String tableName = tableChoice.getSelectedItem();  //指定所要显示的表的名称
    queryFrame frame = new queryFrame(tableName);      //实现显示数据窗口的实例
    frame.show();                                      //显示窗口
  }
}