borrowview.java

代码是自己我的代码不是网上down的。是自己写的。里面有很多值得学习的知识点。还有一些javabean组件。不算自己写的JAR文件

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
public class BorrowView extends JFrame
{
	private ResultSet rs=null;
	private JPanel centerpanel;
	private JPanel southpanel;
	private JLabel username;
	private JLabel bookname;
	private JLabel date;
	private JLabel comment;

	private JTextField myusername;
    private JComboBox mybookname;
    private JTextField mydate;
    private JTextField mycomment;
	JButton ok;
	JButton clear;
	JButton search;
	JButton update;
    
	public BorrowView ()
	{
	centerpanel=new JPanel(new GridLayout(4,2));
	southpanel=new JPanel(new GridLayout(1,1));
	username=new JLabel("借阅者姓名");
	bookname=new JLabel("书  名");
    date=new JLabel("日  期");
	comment=new JLabel("备  注");
	myusername=new JTextField(16);
    mybookname=new JComboBox();
    mydate=new JTextField(16);
    mycomment=new JTextField(16);
	ok=new JButton("添加");
	update=new JButton("更新");
	clear=new JButton("清空");
	search=new JButton("查询");
	centerpanel.add(username);
	centerpanel.add(myusername);
	centerpanel.add(bookname);
	centerpanel.add(mybookname);
	centerpanel.add(date);
	centerpanel.add(mydate);
	centerpanel.add(comment);
	centerpanel.add(mycomment);
	southpanel.add(clear);
	southpanel.add(ok);
	southpanel.add(update);
	southpanel.add(search);
	getContentPane().add(centerpanel,"Center");
	getContentPane().add(southpanel,"South");

	
	String sql;
		sql="select bookname from 书籍借阅信息表 ";
		
		 try
		 {
		 	rs=new DBManager().execute(sql);
		 	while(rs.next())
		 	{
		 	 mybookname.addItem(rs.getString("bookname"));
		 	}
		 }
		 catch(SQLException ex1)
		 {
		 	ex1.printStackTrace();
		 }
		addWindowListener(
			new WindowAdapter()
			{
				public void windowClosing(WindowEvent e)
				{
					System.exit(0);
				}
			
			}
			);
		search.addActionListener(
			new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					Borrowsearch();
				}
			}
			);
		ok.addActionListener(
			new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					BookBorrowAdd();
				}
			}
			);
		clear.addActionListener(
			new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					BookClear();
				}
			}
			);	
			update.addActionListener(
			new ActionListener()
			{
				public void actionPerformed(ActionEvent e)
				{
					BookUpdate();
				}
			}
			);	
		show();
	}

	public void BookBorrowAdd()
	{
		if(myusername.getText().trim().equals(""))
		{
			JOptionPane.showMessageDialog(this,"借阅者姓名不能为空！");
			return;
		}
		else if(mybookname.getSelectedItem().toString().trim().equals(""))
		{
			JOptionPane.showMessageDialog(this,"书名不能为空！");
			return;
		}
		else if(mydate.getText().trim().equals(""))
		{
			JOptionPane.showMessageDialog(this,"借阅日期不能为空！");
			return;
		}
	   else
	   {
	   	BorrowBean bean=new BorrowBean();
		bean.setUsername(myusername.getText().trim());
		bean.setBookname(mybookname.getSelectedItem().toString().trim());
		bean.setBorrowdate(mydate.getText().trim());
	 
	   
	   	 if (bean.insert()) {
            JOptionPane.showMessageDialog(this, "插入成功！");
        } else {
            JOptionPane.showMessageDialog(this, "插入失败！");
        }
	   
	   }
	   }	
	   
	  
		public void Borrowsearch()
		{
		ResultSet rs=null;
		String sql=null;
		if(mybookname.getSelectedItem().toString().trim().length()==0 && myusername.getText().trim().length()==0)
		{
			JOptionPane.showMessageDialog(null,"至少输入一个检索条件！");
			return;
		}
		//定义变量，用来判断是否是第一个查询条件
		boolean isfirst=true;
		//如果学生姓名的查询条件不为空
		if (myusername.getText().trim().length()!=0)
	
		{
			sql="select * from 书籍借阅信息表 where studentname='"+myusername.getText().trim()+"'";
			isfirst=false;
		}
		//如果书名的查询条件不为空
		if(mybookname.getSelectedItem().toString().trim().length()!=0)
		{	//如果是第一个查询条件
			if(isfirst)
			{
			sql="select * from 书籍借阅信息表 where bookname='"+mybookname.getSelectedItem().toString().trim()+"'";	
			}
			else
			{
			sql="select * from 书籍借阅信息表 where studentname='"+myusername.getText().trim()+"' and  bookname='"+mybookname.getSelectedItem().toString().trim()+"'";	
			}
		}
	
		rs=new DBManager().execute(sql);
		try
		{
		if(rs.next())
	    {
	    		myusername.setText(rs.getString("studentname"));
		 		mybookname.setSelectedItem(rs.getString("bookname"));
		 	    mydate.setText(rs.getString("borrowdate"));
		 		mycomment.setText(rs.getString("comment"));
	    }
	    else
	    {
	       JOptionPane.showMessageDialog(this, "没有此记录！");
	    }	
		}
		catch(Exception ex)
		{
			System.out.println(ex.toString());
		}
		}
	public void BookUpdate()
	{
	    BorrowBean bean=new BorrowBean();
		bean.setUsername(myusername.getText().trim());
		bean.setBookname(mybookname.getSelectedItem().toString().trim());
		bean.setBorrowdate(mydate.getText().trim());
		

	

        if (bean.modify()) {
            JOptionPane.showMessageDialog(this, "修改成功！");
        } else {
            JOptionPane.showMessageDialog(this, "修改失败！");
        }
	}
	public void BookClear()
	{
		myusername.setText("");
		mybookname.setSelectedItem("");
		mydate.setText("");
		mycomment.setText("");
	}

}