return.java

用JAVA做的图书借阅信息系统

import java.util.Date;
import java.text.SimpleDateFormat;
import java.sql.*;
import java.awt.*;
import java.awt.event.*;
public class Return extends FrameClass implements ActionListener
{ 
	Label l1,l2,l3,l4,l5;
	TextField t1,t2,t3,t4,t5;
	Button 清空,确定,退出;
	Panel p1,p2,p3;
	Connection con;
    Statement sql1,sql2;
    ResultSet rs1,rs2,rs3;
	Date date=new Date();
	SimpleDateFormat date_format=new SimpleDateFormat("yyyy年MM月dd日");
	String sdate=date_format.format(date);
	boolean b,flag1,flag2,found;
	String reader_name,reader_num,book_num,book_name,borrow_date,return_date,notice;
	String s1,s2,s3,s4,s5,s6,s7,book_num1,reader_num1,return_date1;
	Return()	
    {
		super("读者还书窗口");
		setBounds(150,130,500,300);
		l1=new Label("借阅者编号：");
		l2=new Label("借阅者姓名：");
		l3=new Label("要还书编号：");
		l4=new Label("要还的书名：");
		l5=new Label("  还书日期：");
		t1=new TextField(20);
		t2=new TextField(20);
		t3=new TextField(20);
		t4=new TextField(20);
		t5=new TextField(20);
		清空=new Button("清空");
		确定=new Button("确定");
		退出=new Button("退出");
		l2.setVisible(false);
		t2.setVisible(false);
		l4.setVisible(false);
		t4.setVisible(false);
		t5.setText(sdate);
		清空.addActionListener(this);
		确定.addActionListener(this);
	    退出.addActionListener(this);
	    add(l1);add(l2);add(l3);add(l4);add(l5);
		add(t1);add(t2);add(t3);add(t4);add(t5);
		add(清空);add(确定);add(退出);
		message.setBounds(160,40,230,25);
		l1.setBounds(90,80,80,25);t1.setBounds(180,80,200,25);
		l2.setBounds(90,110,80,25);t2.setBounds(180,110,200,25);
		l3.setBounds(90,140,80,25);t3.setBounds(180,140,200,25);
		l4.setBounds(90,170,80,25);t4.setBounds(180,170,200,25);
		l5.setBounds(90,200,80,25);t5.setBounds(180,200,200,25);	
		清空.setBounds(170,230,50,25);确定.setBounds(220,230,50,25);退出.setBounds(270,230,50,25);
		setVisible(true);
		validate();
		try
	    {
	        Class.forName("com.ms.jdbc.odbc.JdbcOdbcDriver");
	    }
        catch(ClassNotFoundException e1)
	    {
			setMessage("无法连接到数据库！",5000);
			this.dispose();
	    }
        try
		{
			con=DriverManager.getConnection("jdbc:odbc:book","","");
			sql1=con.createStatement();
			sql2=con.createStatement();
		}
		catch(SQLException e2)
		{
			setMessage("没有找到数据库！",3000);
			this.dispose();
		}
	    addWindowListener(new WindowAdapter(){public void windowClosing(WindowEvent e)
		    {
			  setVisible(false);
			  dispose();
		}});
	}
	public void actionPerformed(ActionEvent e)
	{
		if(e.getSource()==确定)
		{
			reader_num=t1.getText().trim();
			book_num=t3.getText().trim();
			return_date=t5.getText().trim();
			reader_num1="'"+reader_num+"'";
			book_num1="'"+book_num+"'";
			//在读者信息表中查找
			try
			{
				flag1=false;
				flag2=false;
				rs1=sql1.executeQuery("SELECT *FROM 读者信息表 WHERE 读者编号="+reader_num1+" AND 书籍标识="+book_num1);
				while(rs1.next())
     			{//找到了
					flag1=true;
					reader_name=rs1.getString("读者姓名");
					book_name=rs1.getString("书籍名称");
					return_date1=rs1.getString("还入日期");
					t2.setText(reader_name);
					t4.setText(book_name);
					l2.setVisible(true);
    		    	t2.setVisible(true);
	    		    l4.setVisible(true);
    		    	t4.setVisible(true);
					if((return_date1.trim().length()>0))
					{
						t5.setText("此书已在"+return_date1+"返还");
						setMessage("该书在此之前已办理了还书手续！",3000);
					}
					else
					{
						sql1.executeUpdate("UPDATE 读者信息表 SET 还入日期="+"'"+return_date+"'"+" WHERE 书籍标识="+book_num1);
						destroy_mark();
						setMessage("该书返还手续已办理完毕！",4000);
	            		t1.setText("");
			            t2.setText("");
			            l2.setVisible(false);
			            t2.setVisible(false);
			            t3.setText("");
			            t4.setText("");
			            l4.setVisible(false);
			            t4.setVisible(false);
			            t5.setText(sdate);
					}
	    		}
			}
			catch(SQLException e3){}
			//没有找到
	    	if(flag1==false)
		    {
				setMessage("读者编号或书籍标识有误！",3000);
				t1.setText("");
    			t2.setText("");
	    		l2.setVisible(false);
		    	t2.setVisible(false);
			    t3.setText("");
		    	t4.setText("");
			    l4.setVisible(false);
		    	t4.setVisible(false);
			    t5.setText(sdate);
	    	}
		}
		if(e.getSource()==清空)
		{
			t1.setText("");
			t2.setText("");
			l2.setVisible(false);
			t2.setVisible(false);
			t3.setText("");
			t4.setText("");
			l4.setVisible(false);
			t4.setVisible(false);
			t5.setText(sdate);
		}
		if(e.getSource()==退出)
		{
			try
			{
				con.close();
			}
			catch(SQLException e4){}
			setVisible(false);
			dispose();
		}
	}
	public void destroy_mark()
	{
		try
		{
			rs2=sql2.executeQuery("SELECT *FROM 书籍信息表 WHERE 标识="+book_num1);
			while(rs2.next())
			{
				sql2.executeUpdate("UPDATE 书籍信息表 SET 借出=false WHERE 标识="+book_num1);
			}
		}
		catch(SQLException e6){	}
	}
}