informationdelete.java

用java刚刚写了不久的学生管理系统

//作者：沈阳
//时间：2008年11月12日
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;
import java.sql.*;
class InformationDelete extends JFrame implements ActionListener{
	int userPriority;
	JComboBox jcbType = new JComboBox();	//删除类型组合框
	JLabel jlabel1= new JLabel("请选择删除类型");
	JTextField txtStudentNumber = new JTextField(14);
	JTextField txtStudentAge1 = new JTextField(6);
	JTextField txtStudentAge2 = new JTextField(6);
	JLabel jlabel2 = new JLabel("请输入学生学号");
	JLabel jlabel3 = new JLabel("请输入年龄范围");
	JButton jbDelete = new JButton("删  除");
	JButton jbExit = new JButton("退  出");
	boolean flag = true;
	InformationDelete(int priority){
		userPriority =  priority;
		Container container = this.getContentPane();
		container.setLayout(new BorderLayout());
		jcbType.addItem("按学生学号删除");
		jcbType.addItem("按年龄范围删除");
		JPanel jpTop = new JPanel();
		JPanel jpTop1 = new JPanel();
		JPanel jpTop2 = new JPanel();	
		jpTop.setLayout(new GridLayout(3,1));
		jpTop1 = new JPanel(new FlowLayout(FlowLayout.LEFT));
		jpTop2 = new JPanel(new FlowLayout(FlowLayout.LEFT));
		JPanel jpBottom = new JPanel();
		JPanel jpBottom1 = new JPanel();
		JPanel jpBottom2 = new JPanel();
		jpBottom.setLayout(new GridLayout(2,1));
		jpBottom2 = new JPanel(new FlowLayout(FlowLayout.CENTER,40,10));
 		jpTop2.add(jlabel1);
		jpTop2.add(jcbType);
		jpTop.add(jpTop1);
		jpTop.add(jpTop2);
		jpBottom2.add(jbDelete);
		jpBottom2.add(jbExit);
		jpBottom.add(jpBottom2);
 		jpBottom.add(jpBottom1);
 		jcbType.addActionListener(this);
 		jbDelete.addActionListener(this);
	 	jbExit.addActionListener(this);
		container.add("North",jpTop);
		container.add("South",jpBottom);	
		Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
		setLocation((screen.width - 380) / 2,(screen.height - 500) / 2);
		setTitle("信息删除");
 		setResizable(false);
		setSize(360,430);
		setVisible(true);
	}
	public void actionPerformed(ActionEvent e){
		Statement stm = null;
    	ResultSet rs = null;
 		Container container = this.getContentPane();
		JPanel jpCenter = new JPanel();		//中部容器
		jpCenter.setLayout(new GridLayout(3,1));	//将中部容器分成两行一列
 		JPanel jpCenterTop = new JPanel();	//取得中部容器的上面一列
 		jpCenterTop = new JPanel(new FlowLayout(FlowLayout.LEFT));	
		if(e.getSource() == jbDelete){
			ConnectServer.mainLink();		//建立和数据库的连接。
			String studentNumber;
			String sql;												
			System.out.println(""+txtStudentNumber.getText());														
	 		if(! txtStudentNumber.getText().equals("")){
				System.out.println("------------------+++-----------------");
				studentNumber = txtStudentNumber.getText();
				try{
					stm = ConnectServer.con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
        			rs = stm.executeQuery("select * from student");
        	 		sql = "DELETE FROM student WHERE stu_number = '"+studentNumber+"'";
	        		System.out.println(""+sql);
	         		stm.executeUpdate(sql);
	        		JOptionPane.showMessageDialog(null,"信息删除成功！");	
	    			txtStudentNumber.setText("");
	    		 	txtStudentNumber.requestFocus();
        			stm.close();		//关闭数据库连接
					ConnectServer.con.close();		
        		}
        		catch(Exception ee){
     				JOptionPane.showMessageDialog(null,"数据库操作失败！");	
     				System.exit(0);
	   			}
	 		}
 	 	  	else if(! txtStudentAge1.getText().equals("")  || ! txtStudentAge2.getText().equals("")){
				System.out.println("*************____************");
				System.out.println(""+txtStudentAge1.getText()+"      "+txtStudentAge2.getText());
				try{
					stm = ConnectServer.con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
        			rs = stm.executeQuery("select * from student");
        	 	 	sql = "DELETE FROM student WHERE stu_age BETWEEN "+txtStudentAge1.getText()+" AND "+txtStudentAge2.getText()+"";								
	        		System.out.println(""+sql);
	           	 	stm.executeUpdate(sql);
	        		JOptionPane.showMessageDialog(null,"信息删除成功！");	
	    			txtStudentAge1.setText("");
	    			txtStudentAge2.setText("");
	    		 	txtStudentAge1.requestFocus();
        			stm.close();		//关闭数据库连接
					ConnectServer.con.close();		
        		}
        		catch(Exception ee){
     				JOptionPane.showMessageDialog(null,"数据库操作失败！");	
     				System.exit(0);
	   			}
 	 		}
		}
		else if(e.getSource() == jcbType){
 			if(jcbType.getSelectedItem().equals("按学生学号删除")){
				jpCenterTop.add(jlabel2);
 				jpCenterTop.add(txtStudentNumber);
 			}
 			else if(jcbType.getSelectedItem().equals("按年龄范围删除")){
 				jpCenterTop.add(jlabel3);
 				jpCenterTop.add(txtStudentAge1);
 				jpCenterTop.add(new JLabel("到"));
 				jpCenterTop.add(txtStudentAge2);
 			}
 			if(flag == false){
 		 		container.remove(2);
			}
			else{
				flag = false;	
			}	
 			jpCenter.add(jpCenterTop);
 			container.add(jpCenter);
 			txtStudentNumber.requestFocus();
			txtStudentAge1.requestFocus();
 			Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
			setLocation((screen.width - 380) / 2,(screen.height - 500) / 2);
			setTitle("信息删除");
 			setResizable(false);
			setSize(360,430);
			setVisible(true);
 		}//else if
		else if(e.getSource() == jbExit){
			dispose();
			new MainWindow(userPriority);	
		}
	}
}