deleterecordframe.java

java数据库编程实例—————————很好很强大第

package deleterecord;
import com.borland.jbcl.layout.*;
import java.awt.*;
import java.awt.event.*;
import java.lang.*;
import java.lang.Object.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;

/**
   * Title:				数据库删除数据记录程序
   * 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 DeleteRecordFrame extends JFrame {
  private JPanel contentPane;
  private XYLayout xYLayout1 = new XYLayout();                 // 构造XYLayout布局管理器
  private TextField delrecordnumField = new TextField();       // 创建显示信息使用的组件
  private Label label1 = new Label();
  private Button deleteButton = new Button();
  private Button refreshButton = new Button();

  Vector vector;                                               // 声明一个向量对象
  String title[] = {"学号","姓名","年龄","性别","系名"};          // 二维表列名
  Connection connection = null;                                // 声明Connection接口对象connection
  ResultSet rSet = null;                                       // 定义数据库查询的结果集
  Statement statement = null;                                  // 定义查询数据库的Statement对象
  AbstractTableModel tm;                                       // 声明一个AbstractTableModel类对象tm

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

  private void jbInit() throws Exception  {
    // 初始化组件
    contentPane = (JPanel) this.getContentPane();
    label1.setText("删除学号：");
    contentPane.setLayout(xYLayout1);
    this.setSize(new Dimension(436, 420));
    this.setTitle("删除数据记录");
    deleteButton.setLabel("删除记录");
    refreshButton.setLabel("刷新记录");
    deleteButton.addActionListener(new java.awt.event.ActionListener() {  // 设置deleteButton按钮监听器
      public void actionPerformed(ActionEvent e) {
        deleteButton_actionPerformed(e);
      }
    });
    refreshButton.addActionListener(new java.awt.event.ActionListener() {  // 设置refreshButton按钮监听器
      public void actionPerformed(ActionEvent e) {
        refreshButton_actionPerformed(e);
      }
    });
    contentPane.add(deleteButton,  new XYConstraints(103, 311, 87, 31));
    contentPane.add(refreshButton,  new XYConstraints(242, 311, 87, 31));
    contentPane.add(delrecordnumField,  new XYConstraints(207, 251, 94, 35));
    contentPane.add(label1,  new XYConstraints(104, 257, 83, 31));
    createtable();                            // 在初始化函数中调用createtable()函数显示表格
   }
   void createtable() {                       // 定义createtable()函数
     JTable table;                            // 声明一个JTable类对象table
     JScrollPane scroll;                      // 声明一个滚动杠对象scroll
     vector = new Vector();                   // 创建向量对象
     tm = new AbstractTableModel() {          // 创建AbstractTableModel类对象tm
       public int getColumnCount() {          // 取得表格列数
         return title.length;
       }
       public int getRowCount() {             // 取得表格行数
         return vector.size();
       }
       public Object getValueAt(int row, int column) {     // 取得单元格中的属性值
         if(!vector.isEmpty()) {
           return ((Vector)vector.elementAt(row)).elementAt(column);
         }
         else {
           return null;
         }
       }
       public void setValueAt(Object value, int row, int column) { // 数据模型不可编辑，该方法设置为空

       }
       public String getColumnName(int column) {           // 取得表格列名
         return title[column];
       }
       public Class getColumnClass(int c) {                // 取得列所属对象类
         return getValueAt(0,c).getClass();
       }
       public boolean isCellEditable(int row, int column) {// 设置单元格不可编辑，为缺省实现
         return false;
       }
     };
     table = new JTable(tm);                               // 生成自己的数据模型
     table.setToolTipText("Display Query Result");         // 设置帮助提示
     table.setAutoResizeMode(table.AUTO_RESIZE_OFF);       // 设置表格调整尺寸模式
     table.setCellSelectionEnabled(false);                 // 设置单元格选择方式
     table.setShowHorizontalLines(true);                   // 设置是否显示单元格之间的分割线
     table.setShowVerticalLines(true);
     scroll = new JScrollPane(table);                      // 给表格加上滚动杠
     scroll.setBounds(6,20,540,250);
     contentPane.add(scroll,new XYConstraints(16, 20, 395, 200));
  }

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

  void deleteButton_actionPerformed(ActionEvent e) {  // 处理deleteButton的ActionEvent
    try {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");  // 实例化JDBC-ODBC桥的驱动
      String url = "jdbc:odbc:TestDbStu";             // 设置连接字符串
      connection = DriverManager.getConnection(url);  // 连接数据库
      // 创建Statement接口对象
      statement = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
      String sql = "select * from studentbase where 学号="+Integer.parseInt(delrecordnumField.getText()) ;
      rSet = statement.executeQuery(sql);             // 执行学号为输入学号的查询语句
      if (rSet.next()==false) {                       // 判断数据库中是否有要删除的记录，如没有则显示提示框
        JOptionPane msg = new JOptionPane();
        JOptionPane.showMessageDialog(DeleteRecordFrame.this, "数据库中没有您删除的学号", "数据库中没有您删除的学号！", 1);
      }
      else {
        sql="delete from studentbase where 学号="+Integer.parseInt(delrecordnumField.getText());
        statement.executeUpdate(sql);                // 执行删除数据记录语句
        delrecordnumField.setText("");               // 清空输入的学号
      }
    }
    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(statement != null) {
          statement.close();                       // 关闭Statement接口实例
        }
        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 refreshButton_actionPerformed(ActionEvent e) { // 处理refreshButton的ActionEvent
    try {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");  // 实例化JDBC-ODBC桥的驱动
      String url = "jdbc:odbc:TestDbStu";
      connection = DriverManager.getConnection(url);  // 连接数据库
      statement = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
      String sql = "select * from studentbase";
      rSet = statement.executeQuery(sql);             // 执行查询语句
      vector.removeAllElements();                     // 初始化向量对象
      tm.fireTableStructureChanged();                 // 更新表格内容
      while(rSet.next()) {
        Vector rec_vector = new Vector();
        // 从结果集中取数据放入向量rec_vector中
        rec_vector.addElement(String.valueOf(rSet.getInt("学号")));
        rec_vector.addElement(rSet.getString("姓名"));
        rec_vector.addElement(String.valueOf(rSet.getInt("年龄")));
        rec_vector.addElement(rSet.getString("性别"));
        rec_vector.addElement(rSet.getString("系名"));
        vector.addElement(rec_vector);                // 向量rec_vector加入向量vector中
      }
      tm.fireTableStructureChanged();                 // 更新表格，显示向量vector的内容
      rSet.close();                                   // 关闭结果集
    }
    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(statement != null) {
          statement.close();                          // 关闭Statement接口实例
        }
        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());
      }
    }
  }
}