exercise25_1.java

这是一个简单的基于JAVA的数据库系统

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

public class Exercise25_1 extends javax.swing.JApplet {
  ResultSet resultSet;
  int currentRowNumber;
  public Exercise25_1() {
    initComponents();
    initializeDB();
  }
  private void initComponents() {
    jPanel1 = new javax.swing.JPanel();
    jbtFirst = new javax.swing.JButton();
    jbtNext = new javax.swing.JButton();
    jbtPrior = new javax.swing.JButton();
    jbtLast = new javax.swing.JButton();
    jbtInsert = new javax.swing.JButton();
    jbtDelete = new javax.swing.JButton();
    jbtUpdate = new javax.swing.JButton();
    jlblStatus = new javax.swing.JLabel();
    jpAddress = new javax.swing.JPanel();
    jPanel2 = new javax.swing.JPanel();
    jLabel1 = new javax.swing.JLabel();
    jtfFirstName = new javax.swing.JTextField();
    jLabel2 = new javax.swing.JLabel();
    jtfMI = new javax.swing.JTextField();
    jLabel3 = new javax.swing.JLabel();
    jtfLastName = new javax.swing.JTextField();
    jPanel3 = new javax.swing.JPanel();
    jLabel4 = new javax.swing.JLabel();
    jtfStreet = new javax.swing.JTextField();
    jPanel4 = new javax.swing.JPanel();
    jLabel5 = new javax.swing.JLabel();
    jtfCity = new javax.swing.JTextField();
    jLabel6 = new javax.swing.JLabel();
    jtfState = new javax.swing.JTextField();
    jLabel7 = new javax.swing.JLabel();
    jtfZip = new javax.swing.JTextField();
    jPanel5 = new javax.swing.JPanel();
    jLabel8 = new javax.swing.JLabel();
    jtfTelephone = new javax.swing.JTextField();
    jPanel6 = new javax.swing.JPanel();
    jLabel9 = new javax.swing.JLabel();
    jtfEmail = new javax.swing.JTextField();

    jbtFirst.setText("First");
    jbtFirst.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtFirstActionPerformed(evt);
      }
    });
    jPanel1.add(jbtFirst);
    jbtNext.setText("Next");
    jbtNext.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtNextActionPerformed(evt);
      }
    });
    jPanel1.add(jbtNext);
    jbtPrior.setText("Prior");
    jbtPrior.addActionListener(new java.awt.event.ActionListener() {
	  public void actionPerformed(java.awt.event.ActionEvent evt) {
	    jbtPriorActionPerformed(evt);
	  }
    });

    jPanel1.add(jbtPrior);

    jbtLast.setText("Last");
    jbtLast.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtLastActionPerformed(evt);
      }
    });

    jPanel1.add(jbtLast);

    jbtInsert.setText("Insert");
    jbtInsert.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtInsertActionPerformed(evt);
      }
    });

    jPanel1.add(jbtInsert);

   //--------------
   jbtDelete.setText("Delete");
    jbtDelete.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtDeleteActionPerformed(evt);
      }
    });
//---------------
    jPanel1.add(jbtDelete);

    jbtUpdate.setText("Update");
    jbtUpdate.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(java.awt.event.ActionEvent evt) {
        jbtUpdateActionPerformed(evt);
      }
    });

    jPanel1.add(jbtUpdate);
    getContentPane().add(jPanel1, java.awt.BorderLayout.NORTH);
    jlblStatus.setText("jLabel1");
    getContentPane().add(jlblStatus, java.awt.BorderLayout.SOUTH);
    jpAddress.setLayout(new java.awt.GridLayout(5, 0));
    jPanel2.setLayout(new java.awt.FlowLayout(java.awt.FlowLayout.LEFT));
    jLabel1.setText("First Name");
    jPanel2.add(jLabel1);
    jtfFirstName.setColumns(10);
    jPanel2.add(jtfFirstName);
    jLabel2.setText("MI");
    jPanel2.add(jLabel2);
    jtfMI.setColumns(2);
    jPanel2.add(jtfMI);
    jLabel3.setText("Last Name");
    jPanel2.add(jLabel3);
    jtfLastName.setColumns(15);
    jPanel2.add(jtfLastName);
    jpAddress.add(jPanel2);
    jPanel3.setLayout(new java.awt.FlowLayout(java.awt.FlowLayout.LEFT));
    jLabel4.setText("Street");
    jPanel3.add(jLabel4);
    jtfStreet.setColumns(40);
    jPanel3.add(jtfStreet);
    jpAddress.add(jPanel3);
    jPanel4.setLayout(new java.awt.FlowLayout(java.awt.FlowLayout.LEFT));
    jLabel5.setText("City");
    jPanel4.add(jLabel5);
    jtfCity.setColumns(15);
    jPanel4.add(jtfCity);
    jLabel6.setText("State");
    jPanel4.add(jLabel6);
    jtfState.setColumns(2);
    jPanel4.add(jtfState);
    jLabel7.setText("ZIP");
    jPanel4.add(jLabel7);
    jtfZip.setColumns(5);
    jPanel4.add(jtfZip);
    jpAddress.add(jPanel4);
    jPanel5.setLayout(new java.awt.FlowLayout(java.awt.FlowLayout.LEFT));
    jLabel8.setText("Telephone");
    jPanel5.add(jLabel8);
    jtfTelephone.setColumns(12);
    jPanel5.add(jtfTelephone);
    jpAddress.add(jPanel5);
    jPanel6.setLayout(new java.awt.FlowLayout(java.awt.FlowLayout.LEFT));
    jLabel9.setText("Email");
    jPanel6.add(jLabel9);
    jtfEmail.setColumns(25);
    jPanel6.add(jtfEmail);
    jpAddress.add(jPanel6);
    getContentPane().add(jpAddress, java.awt.BorderLayout.CENTER);
  }

  private void jbtUpdateActionPerformed(java.awt.event.ActionEvent evt) {
    try
    {
      updateRecord();
      resultSet.updateRow();
    }
    catch (Exception ex)
    {
      jlblStatus.setText(ex.toString());
    }
  }
   //----------------
  private void jbtDeleteActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      resultSet.deleteRow();
      jlblStatus.setText("Deletion succeeded");
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }
  //------------------------
  private void jbtInsertActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      insert();
      jlblStatus.setText("Insertion succeeded");
    }
    catch (SQLException ex) {
      jlblStatus.setText(ex.getMessage());
    }
  }
  private void jbtLastActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      if (resultSet.last())
        showRecord();
      else
        jlblStatus.setText("There is no row in the result set");
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }

  private void jbtPriorActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      if (resultSet.isFirst())
        jlblStatus.setText("This is already the first row");
      else {
        resultSet.previous();
        showRecord();
      }
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }
  private void jbtNextActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      if (resultSet.isLast())
        jlblStatus.setText("This is already the last row");
      else {
        resultSet.next();
        showRecord();
      }
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }
  private void jbtFirstActionPerformed(java.awt.event.ActionEvent evt) {
    try {
      if (resultSet.first())
        showRecord();
      else
        jlblStatus.setText("There is no row in the result set");
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }
  private void initializeDB() {
    try {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
      System.out.println("Driver loaded");
      Connection connection = DriverManager.getConnection("jdbc:odbc:exampleMDBDataSource", "", "");
      System.out.println("Database connected");
      Statement statement = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
      resultSet = statement.executeQuery("select * from Address");
      resultSet.first();
      showRecord();
    }
    catch (Exception ex) {
      jlblStatus.setText(ex.toString());
    }
  }
  private void showRecord() throws Exception {
    jtfFirstName.setText(resultSet.getString("firstName"));
    jtfLastName.setText(resultSet.getString("lastName"));
    jtfMI.setText(resultSet.getString("mi"));
    jtfStreet.setText(resultSet.getString("Street"));
    jtfCity.setText(resultSet.getString("City"));
    jtfState.setText(resultSet.getString("State"));
    jtfTelephone.setText(resultSet.getString("Telephone"));
    jtfZip.setText(resultSet.getString("zip"));
    jtfEmail.setText(resultSet.getString("email"));

    currentRowNumber = resultSet.getRow();
    jlblStatus.setText("Current row number: " + currentRowNumber);
  }
  public static void main(String[] args) {
    Exercise25_1 applet = new Exercise25_1();
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(3);
    frame.setTitle("Exercise25_1");
    frame.getContentPane().add(applet, BorderLayout.CENTER);
    applet.init();
    applet.start();
    frame.pack();
    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    frame.setLocation((d.width - frame.getSize().width) / 2, (d.height - frame.getSize().height) / 2);
    frame.setVisible(true);
  }
  protected void insert() throws SQLException {
    updateRecord();
    resultSet.insertRow();
    resultSet.moveToCurrentRow();
  }
  protected void updateRecord() throws SQLException {
   resultSet.updateString("firstName",jtfFirstName.getText().trim());
    resultSet.updateString("MI", jtfMI.getText().trim());
    resultSet.updateString("lastName", jtfLastName.getText().trim());
    resultSet.updateString("Street", jtfStreet.getText().trim());
    resultSet.updateString("City", jtfCity.getText().trim());
    resultSet.updateString("zip", jtfZip.getText().trim());
    resultSet.updateString("Telephone",jtfTelephone.getText().trim());
    resultSet.updateString("email", jtfEmail.getText().trim());
  }
  private javax.swing.JTextField jtfStreet;
  private javax.swing.JTextField jtfLastName;
  private javax.swing.JPanel jPanel6;
  private javax.swing.JPanel jPanel5;
  private javax.swing.JPanel jPanel4;
  private javax.swing.JPanel jPanel3;
  private javax.swing.JTextField jtfMI;
  private javax.swing.JPanel jPanel2;
  private javax.swing.JPanel jPanel1;
  private javax.swing.JButton jbtLast;
  private javax.swing.JButton jbtPrior;
  private javax.swing.JTextField jtfCity;
  private javax.swing.JTextField jtfZip;
  private javax.swing.JButton jbtUpdate;
  private javax.swing.JTextField jtfEmail;
  private javax.swing.JTextField jtfFirstName;
  private javax.swing.JLabel jlblStatus;
  private javax.swing.JTextField jtfState;
  private javax.swing.JButton jbtInsert;
  private javax.swing.JButton jbtFirst;
  private javax.swing.JLabel jLabel9;
  private javax.swing.JButton jbtNext;
  private javax.swing.JLabel jLabel8;
  private javax.swing.JPanel jpAddress;
  private javax.swing.JLabel jLabel7;
  private javax.swing.JLabel jLabel6;
  private javax.swing.JLabel jLabel5;
  private javax.swing.JLabel jLabel4;
  private javax.swing.JLabel jLabel3;
  private javax.swing.JTextField jtfTelephone;
  private javax.swing.JLabel jLabel2;
  private javax.swing.JLabel jLabel1;
  private javax.swing.JButton jbtDelete;
}