createtableframe.java

Java数据库编程实例（2）

package createtable;
import com.borland.jbcl.layout.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.*;

/**
   * Title:				创建数据库中的表程序
   * 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 CreateTableFrame extends JFrame {
  private XYLayout xYLayout1 = new XYLayout();           // 构造XYLayout布局管理器
  private JPanel contentPane;

  // 创建显示信息使用的组件
  private Label label1 = new Label();
  private TextField tablenameField = new TextField();
  private Label label2 = new Label();
  private TextField columnname1Field = new TextField();
  private TextField columnname2Field = new TextField();
  private TextField columnname3Field = new TextField();
  private Label label3 = new Label();
  private Choice column1typechoice = new Choice();
  private Choice column2typechoice = new Choice();
  private Choice column3typechoice = new Choice();
  private Label label4 = new Label();
  private Checkbox checkbox1 = new Checkbox();
  private Checkbox checkbox2 = new Checkbox();
  private Checkbox checkbox3 = new Checkbox();
  private CheckboxGroup checkboxGroup1 = new CheckboxGroup();
  private Button creattableButton = new Button();

  Connection connection = null;                      // 声明Connection接口对象connection
  Statement statement = null;                        // 定义查询数据库的Statement对象

  // 定义字段类型字符串变量
  String column1type;
  String column2type;
  String column3type;

  String sql;                         // 定义SQL语句字符串变量

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

  private void jbInit() throws Exception  {
    contentPane = (JPanel) this.getContentPane();
    // 初始化组件
    label1.setText("创建表名称：");
    contentPane.setLayout(xYLayout1);
    this.setSize(new Dimension(400, 300));
    this.setTitle("创建数据库中的表");
    label2.setText("字段名：");
    label3.setText("字段类型：");
    label4.setText("主  键：");
    checkbox1.setCheckboxGroup(checkboxGroup1);
    checkbox1.setLabel("字段1");
    checkbox1.addItemListener(new java.awt.event.ItemListener() {    // checkbox1的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        checkbox1_itemStateChanged(e);
      }
    });
    checkbox2.setCheckboxGroup(checkboxGroup1);
    checkbox2.setLabel("字段2");
    checkbox2.addItemListener(new java.awt.event.ItemListener() {    // checkbox2的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        checkbox2_itemStateChanged(e);
      }
    });
    checkbox3.setCheckboxGroup(checkboxGroup1);
    checkbox3.setLabel("字段3");
    checkbox3.addItemListener(new java.awt.event.ItemListener() {    // checkbox3的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        checkbox3_itemStateChanged(e);
      }
    });
    checkboxGroup1.setSelectedCheckbox(null);
    creattableButton.setLabel("创建表");
    creattableButton.addActionListener(new java.awt.event.ActionListener() {   // creattableButton的事件监听方法
      public void actionPerformed(ActionEvent e) {
        creattableButton_actionPerformed(e);
      }
    });
    column1typechoice.addItemListener(new java.awt.event.ItemListener() {      // column1typechoice的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        column1typechoice_itemStateChanged(e);
      }
    });
    column2typechoice.addItemListener(new java.awt.event.ItemListener() {      // column2typechoice的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        column2typechoice_itemStateChanged(e);
      }
    });
    column3typechoice.addItemListener(new java.awt.event.ItemListener() {      // column3typechoice的事件监听方法
      public void itemStateChanged(ItemEvent e) {
        column3typechoice_itemStateChanged(e);
      }
    });
    contentPane.add(tablenameField,  new XYConstraints(156, 35, 88, 29));
    contentPane.add(columnname2Field, new XYConstraints(204, 90, 70, 28));
    contentPane.add(label2,  new XYConstraints(47, 88, 69, 28));
    contentPane.add(columnname1Field, new XYConstraints(121, 90, 70, 28));
    contentPane.add(columnname3Field, new XYConstraints(286, 90, 70, 28));
    contentPane.add(column2typechoice, new XYConstraints(206, 139, 73, 27));
    contentPane.add(label3,  new XYConstraints(47, 142, 64, 24));
    contentPane.add(column1typechoice, new XYConstraints(121, 139, 73, 27));
    contentPane.add(column3typechoice, new XYConstraints(290, 139, 73, 27));
    contentPane.add(checkbox2, new XYConstraints(214, 182, 76, 30));
    contentPane.add(label4,  new XYConstraints(47, 184, 45, 30));
    contentPane.add(checkbox1, new XYConstraints(124, 182, 76, 30));
    contentPane.add(checkbox3, new XYConstraints(303, 182, 76, 30));
    contentPane.add(creattableButton,    new XYConstraints(153, 216, 94, 34));
    contentPane.add(label1, new XYConstraints(47, 36, 81, 24));
    // 向choice控件中添加项
    column2typechoice.insert(" ",0) ;
    column3typechoice.insert(" ",0) ;
    column1typechoice.insert(" ",0) ;
    column1typechoice.insert("文本",1) ;
    column2typechoice.insert("文本",1) ;
    column3typechoice.insert("文本",1) ;
    column1typechoice.insert("数字",2) ;
    column2typechoice.insert("数字",2) ;
    column3typechoice.insert("数字",2) ;
  }

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

  void checkbox1_itemStateChanged(ItemEvent e) {               // 处理checkbox1事件
    sql="create table  "+tablenameField.getText()+ "("+columnname1Field.getText()+" "+column1type+" constraint "+columnname1Field.getText()+" primary key, "+columnname2Field.getText()+" "+column2type+", "+columnname3Field.getText()+" "+column3type+")" ;
  }

  void checkbox2_itemStateChanged(ItemEvent e) {               // 处理checkbox2事件
    sql="create table  "+tablenameField.getText()+ "("+columnname1Field.getText()+" "+column1type+", "+columnname2Field.getText()+" "+column2type+" constraint "+columnname2Field.getText()+" primary key, "+columnname3Field.getText()+" "+column3type+")" ;
  }
  void checkbox3_itemStateChanged(ItemEvent e) {               // 处理checkbox3事件
    sql="create table  "+tablenameField.getText()+ "("+columnname1Field.getText()+" "+column1type+", "+columnname2Field.getText()+" "+column2type+", "+columnname3Field.getText()+" "+column3type+" constraint "+columnname1Field.getText()+" primary key "+")" ;
  }

  void creattableButton_actionPerformed(ActionEvent e) {       // 处理creattableButton事件
    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
      statement = connection.createStatement();
      statement.executeUpdate(sql);                            // 执行创建数据库表语句
      // 清空文本框
      tablenameField.setText("");
      columnname1Field.setText("");
      columnname2Field.setText("");
      columnname3Field.setText("");
    }
    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 column1typechoice_itemStateChanged(ItemEvent e) {       // 处理column1typechoice事件，以确定字段类型
    switch (column1typechoice.getSelectedIndex()){
      case 1:column1type="varchar(30)";
             break;
      case 2:column1type="int";
             break;
    }
  }

  void column2typechoice_itemStateChanged(ItemEvent e) {       // 处理column2typechoice事件，以确定字段类型
    switch (column2typechoice.getSelectedIndex()){
      case 1: column2type="varchar(30)";
              break;
      case 2: column2type="int";
              break;
    }
  }

  void column3typechoice_itemStateChanged(ItemEvent e) {       // 处理column3typechoice事件，以确定字段类型
    switch (column3typechoice.getSelectedIndex()){
      case 1: column3type="varchar(30)";
              break;
      case 2: column3type="int";
              break;
    }
  }
}