courseframe.java

java程序 学生信息管理系统 数据库采用acce

package com.studentFrame;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JPanel;
import javax.swing.*;
import java.sql.*;

/*课程信息管理窗口*/
public class CourseFrame extends JFrame implements ItemListener,ActionListener  
 	 {
		 String s = " 课程名               性质     教师      学时      学分";
		 Label prompt;
		 Choice term;   //学期的下拉列表框
		 Panel p;
		 TextArea ta;
		 JButton inquire;
		 String tempterm = "2005-1";     //默认学期为2005-1
		 String id;
 		 CourseFrame(String ID)
 		 {
 		 	 id = ID;
			 prompt = new Label("请选择查询学期");
			 term = new Choice();
			 term.add("2005-1");
			 term.add("2005-2");
			 term.add("2006-1");
			 term.add("2006-2");
			 inquire = new JButton("查询");
			 p = new Panel();
			 p.add(prompt);
			 p.add(term);
			 p.add(inquire);
			 ta = new TextArea();
			 ta.setEditable(false);
			 ta.setFont(new Font("TimesRoman",Font.BOLD,12));
			 this.getContentPane().add(p,BorderLayout.NORTH);
			 this.getContentPane().add(ta,BorderLayout.CENTER);
			 term.addItemListener(this);
			 inquire.addActionListener(this);
 			 setSize(500,300);
 			 setLocation(300,300);
 			 setVisible(true);
 		//	 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 	    }
 	   public void actionPerformed(ActionEvent e)
 	   {   
 	      String url="jdbc:odbc:javadbc";
	      String username="";
	      String password="";
 	      Connection con =null;
	      Statement stmt = null;
	      ResultSet rs = null;
	      String sql,result;
	      boolean hasrecord = false;    //标志是否有记录
	      ta.append("课程名     课程性质     学时      学分    教师      地点    \n");
		  try{
		  	 /*连接数据库*/
		      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
	          con=DriverManager.getConnection(url,username,password);
	          stmt=con.createStatement();
	          sql = "select course.cname,property,studytime,credit,teacher,place from "
	                 +"course,cschedule where course.cname=cschedule.cname and course.term='"
	                 +tempterm+"' and cschedule.grade in"+"(select grade from student where id ='"
	                 +id+"')";
	          rs = stmt.executeQuery(sql);
	          while(rs.next())
	          {
	          	/*显示查询到的课程信息*/
	          	result = rs.getString(1)+"       "+rs.getString(2)+"      "+rs.getInt(3)+
	          	         "       "+rs.getFloat(4)+"      "+rs.getString(5)+"      "+rs.getString(6);
	          	/*将查询的课程信息添加到文本域*/
	          	ta.append(result+"\n");
	          	hasrecord = true;
	          }
	         }
	      catch(SQLException ex)
	       {
	       	System.out.println(ex.getMessage());
	       }
	      catch(Exception e1) {} 
	      /*关闭数据库连接*/    	       
	      finally{
        	      try
        	      {
        	      	if(stmt!=null)
                      stmt.close();
                    con.close();
        	      }
        	     catch(SQLException ex)
                 {
 	                ex.printStackTrace();
                 }   
                 }
          if(!hasrecord)
	        JOptionPane.showMessageDialog(null,"暂无课程");	
	        inquire.setEnabled(false);       
	   }
	   /*判断查询的学期*/
	   public void itemStateChanged(ItemEvent e1)
	   {
		   Choice temp;
		   if(e1.getItemSelectable() instanceof Choice)
		   {
			   temp = (Choice)(e1.getItemSelectable());
			   tempterm = temp.getSelectedItem();
		   }
	   }
	}