renewbookcard.java

这是一个用jbuilder2005编写的图书管理系统

package bookmanage;

import java.awt.*;
import javax.swing.*;
import java.awt.Rectangle;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * <p>Title: 图书管理系统</p>
 *
 * <p>Description: 此类主要是用来恢复一个同学的借书卡</p>
 *
 * <p>Copyright: Copyright (c) 2006</p>
 *
 * <p>Company: 浙江工业大学信息学院计算机系</p>
 *
 * @author 曾文秋
 * @version 1.0
 */
public class RenewBookCard
    extends JDialog {
  JPanel panel1 = new JPanel();
  JLabel jLabel1 = new JLabel();
  JTextField jTextFieldXuehao = new JTextField();
  JButton jButtonRenew = new JButton();
  String strSQL="";
  ResultSet rs;
  //定义数据库操作对象
  private DBManager db = new DBManager();
  String xh="";

  public RenewBookCard(Frame owner, String title, boolean modal) {
    super(owner, title, modal);
    try {
      setDefaultCloseOperation(DISPOSE_ON_CLOSE);
      jbInit();
      pack();
    }
    catch (Exception exception) {
      exception.printStackTrace();
    }
  }

  public RenewBookCard() {
    this(new Frame(), "RenewBookCard", false);
  }

  private void jbInit() throws Exception {
    panel1.setLayout(null);
    jLabel1.setText("学号：");
    jLabel1.setBounds(new Rectangle(35, 22, 42, 15));
    jTextFieldXuehao.setBounds(new Rectangle(80, 20, 103, 20));
    jButtonRenew.setBounds(new Rectangle(203, 19, 84, 23));
    jButtonRenew.setText("取消挂失");
    jButtonRenew.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        jButtonRenew_actionPerformed(e);
      }
    });
    getContentPane().add(panel1);
    panel1.add(jButtonRenew);
    panel1.add(jLabel1);
    panel1.add(jTextFieldXuehao);
  }

  public void jButtonRenew_actionPerformed(ActionEvent e) {
    xh=jTextFieldXuehao.getText().trim();
    if(xh.equals("")){
      JOptionPane.showMessageDialog(this, "学号不能为空！");
      return;
    }
    strSQL="select * from buser where xuehao='"+xh+"'";
    rs = db.getResult(strSQL);
    boolean isexist = false;
    try {
      isexist = rs.first();
    }
    catch (SQLException ex1) {
    }
    //若书名存在，提示警告信息
    if (!isexist){
      JOptionPane.showMessageDialog(this, "这个学生不存在！");
      return;
    }
    strSQL="update buser set hangUp=0 where xuehao='"+xh+"'";
    if (db.executeSql(strSQL)) {
      JOptionPane.showMessageDialog(this, "成功修改！");
      this.dispose();
    }
    else {
      JOptionPane.showMessageDialog(this, " 修改失败");

    }
    db.close();



  }
}