bookdel.java

java 开发的图书管理系统~~~。可以实现很多功能

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

public class BookDel extends JFrame implements ActionListener
{
	public BookDel()
	{
		setTitle("删除书籍信息");
		setSize(200,200);
		gl=new GridLayout(7,2,20,20);
		gl2=new GridLayout(1,4,20,20);
		JPanel panel=new JPanel();
		JPanel panel2=new JPanel();
		panel.setLayout(gl);
		panel2.setLayout(gl2);
		booknamelbl=new JLabel("名称(输入书名按确认显示相关内容)");
	 	publicnamelbl=new JLabel("出版社");
	 	authorlbl=new JLabel("作者");
	 	addresslbl=new JLabel("地址");
	 	publicdatelbl=new JLabel("出版日期");
	 	pricelbl=new JLabel("价钱");
	 	detaillbl=new JLabel("备注");
	  booknametex=new JTextField("");
 		publicnametex=new JTextField("");
 		authortex=new JTextField("");;
 		addresstex=new JTextField("");
 		publicdatetex=new JTextField("");
 		pricetex=new JTextField("");
 		detailtex=new JTextArea("");
		editbtn=new JButton("删除");
		surebtn=new JButton("确定");
		cleanbtn=new JButton("清空");
		cancelbtn=new JButton("退出");
		panel.add(booknamelbl);
		panel.add(booknametex);
		panel.add(publicnamelbl);
		panel.add(publicnametex);
		panel.add(authorlbl);
		panel.add(authortex);
		panel.add(addresslbl);
		panel.add(addresstex);
		panel.add(publicdatelbl);
		panel.add(publicdatetex);
		panel.add(pricelbl);
		panel.add(pricetex);
		panel.add(detaillbl);
		panel.add(detailtex);
		panel2.add(cleanbtn);
		panel2.add(surebtn);
		panel2.add(editbtn);
		panel2.add(cancelbtn);
		cleanbtn.addActionListener(this);
		surebtn.addActionListener(this);
		cancelbtn.addActionListener(this);		
		editbtn.addActionListener(this);
		getContentPane().add(panel,BorderLayout.CENTER);
		getContentPane().add(panel2,BorderLayout.SOUTH);
	}
	public void actionPerformed(ActionEvent e)
	{
		Object source=e.getSource();
		if(source==surebtn)
		{
			String bookname=new String(booknametex.getText()).trim();
			if(bookname.equals(""))
			{
			JOptionPane.showMessageDialog(null,"书名不能为空!");
			return;
			}
			String strsql;
		//查询是否已经存在
		strsql=("select * from book where bookname='"+bookname+"'");
		System.out.println(strsql);
		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);
			}
		if(!isexist){
			JOptionPane.showMessageDialog(null,"没有此书");
			return;
		}
		//显示书的详细内容
		else{
			try
			{
			booknametex.setText(rs.getString(2));
			publicnametex.setText(rs.getString(3));
			authortex.setText(rs.getString(4));
			addresstex.setText(rs.getString(5));
			//把float包装成Float类再变成字符串输出
			pricetex.setText(new Float(rs.getFloat(7)).toString());
			publicdatetex.setText(rs.getString(6));
			detailtex.setText(rs.getString(8));
		}
		catch(SQLException e2)
		{
			System.out.println(e2);
		}
		
			}
		}
		if(source==editbtn)
		{	
			String bookname=new String(booknametex.getText()).trim();
			if(bookname.equals(""))
			{
			JOptionPane.showMessageDialog(null,"书名不能为空!");
			return;
			}
		String authorname=new String(authortex.getText()).trim();
			if(authorname.equals(""))
			{
			authorname="不详";
			}
			String publicdate=new String(publicdatetex.getText()).trim();
			if(publicdate.equals(""))
			{
			publicdate="不详";
			}
			String address=new String(addresstex.getText()).trim();
			if(address.equals(""))
			{
			address="不详";
			}
		String  publicname=new String(publicnametex.getText()).trim();
		if(publicname.equals(""))
		{
			JOptionPane.showMessageDialog(null,"出版社名不能为空!");
			return;
		}
		String price=new String(pricetex.getText()).trim();
		
		if(price.equals(""))
		{
			JOptionPane.showMessageDialog(null,"价格不能为空");
			return;
		}
		Float fprice=new Float(price);
		String detail=new String(detailtex.getText()).trim();
		if(detail.equals(""))
			{
				detail=" ";
			}
			//确认是否删除
		int confirm=JOptionPane.showConfirmDialog(null,"是否删除?","删除确认",JOptionPane.YES_NO_OPTION);
		if(confirm==JOptionPane.YES_OPTION)
		{
			String strsql;
			strsql=("delete from book where bookname='"+bookname+"' and press='"+publicname+"' and price="+fprice);
			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;
		}
		if(source==cleanbtn)
		{
			booknametex.setText("");
			publicnametex.setText("");
			authortex.setText("");
			addresstex.setText("");
			publicdatetex.setText("");
			pricetex.setText("");
			detailtex.setText("");
			return;
		}
	}
	private JLabel booknamelbl;
	private JLabel publicnamelbl;
	private JLabel authorlbl;
	private JLabel addresslbl;
	private JLabel publicdatelbl;
	private JLabel pricelbl;
	private JLabel detaillbl;
	private JTextField booknametex;
	private JTextField publicnametex;
	private JTextField authortex;
	private JTextField addresstex;
	private JTextField publicdatetex;
	private JTextField pricetex;
	private JTextArea detailtex;
	private JButton surebtn;
	private JButton editbtn;
	private JButton cleanbtn;
	private JButton cancelbtn;
	private GridLayout gl;
	private GridLayout gl2;
	private DBManager db=new DBManager();
	private ResultSet rs;
}