userdel.java

实现图书借阅管理,运用access数据库

package bookmanager;
import javax.swing.*;
import java.awt.event.*;
import java.awt.GridLayout;
import java.sql.*;

public class userDel extends JFrame implements ActionListener
{
	public userDel()
	{
		setTitle("删除用户");
		setSize(200,200);
		gl=new GridLayout(3,2,20,20);
		JPanel panel=new JPanel();
		panel.setLayout(gl);
		userlbl=new JLabel("用户名");
		passwordlbl=new JLabel("密码");
		usertex=new JTextField("");
		passwordtex=new JPasswordField("");
		addbtn=new JButton("确认");
		cancelbtn=new JButton("取消");
		panel.add(userlbl);
		panel.add(usertex);
		panel.add(passwordlbl);
		panel.add(passwordtex);
		panel.add(addbtn);
		panel.add(cancelbtn);
		getContentPane().add(panel);
		addbtn.addActionListener(this);
		cancelbtn.addActionListener(this);
		
		
	}
	public void actionPerformed(ActionEvent e)
	{
		Object source=e.getSource();
		if(source==addbtn)
		{
			String username=usertex.getText().trim();
			if(username.equals(""))
			{
			JOptionPane.showMessageDialog(null,"用户名不能为空!");
			return;
		}
		String  password=new String(passwordtex.getPassword()).trim();
		if(password.equals(""))
		{
			JOptionPane.showMessageDialog(null,"密码名不能为空!");
			return;
		}
		String strsql;
		//查询密码与用户名匹配的一项
		strsql=("select * from admin where Username='"+usertex.getText().trim()+"'and Password='"+password+"'");
		rs=db.getResult(strsql);
		
		boolean isexist=false;
		try{
			//把游标指向结果集的第一行，如果没有数据则返回false
			isexist=rs.first();		
		}
		catch(SQLException w)
		{
			System.out.println(w);}
		//判断结果是否正确
		if(!isexist){
			JOptionPane.showMessageDialog(null,"用户名不存在,或密码不正确");
			passwordtex.setText("");
			return;
		}
		else{
			int confirm=JOptionPane.showConfirmDialog(null,"是否删除?","删除确认",JOptionPane.YES_NO_OPTION);
			if(confirm==JOptionPane.YES_OPTION)
			{ 
				strsql=("delete from admin where username='"+username+"'");
				System.out.println(strsql);
				boolean success=db.executeSql(strsql);
				if(!success)
				{
					JOptionPane.showMessageDialog(null,"修改不成功，请重试");
				}
				else
					JOptionPane.showMessageDialog(null,"修改成功");
				
		
			this.dispose();	
			}
			else
			{
				this.dispose();
				return;
			}
		
		}
	}
		if(source==cancelbtn)
		{
			
			this.dispose();
			return;
		}
	
	}
	private JLabel userlbl;
	private JLabel passwordlbl;
	private JTextField usertex;
	private JPasswordField passwordtex;
	private JButton addbtn;
	private JButton cancelbtn;
	private GridLayout gl;
	private DBManager db=new DBManager();
	private ResultSet rs;
}