classp.java

学生可以选课

import java.sql.*;

public class classp  
{

  private String id;

  private String cour_id;

  private String tea_id;
 
 private String room_id;
 
 private String cour_time;
 
 public String getId() {
  
  return id;
 
 }

  public void setId(String id) {
 
   this.id = id;

  }
 
 public String getCour_id() {
  
  return cour_id;

  }
 
 public void setCour_id(String cour_id) {
  
  this.cour_id = cour_id;
 
 }
 
 public String getTea_id() {

    return tea_id;
 
 }
 
 public void setTea_id(String tea_id) {
   
 this.tea_id = tea_id;
 
 }
 
 public String getRoom_id() {
 
   return room_id;

  }
 
 public void setRoom_id(String room_id) {
  
  this.room_id = room_id;
 
 }

  public String getCour_time() {
   
 return cour_time;
 
 }
 
 public void setCour_time(String time) {
   
 this.cour_time = time;
 
 }

  

  public ResultSet getTeachers(){
  
	String sql="select id,name from teacher  ";
 
 	sqlBean db = new sqlBean();
  
	ResultSet rs = db.executeQuery(sql);
 
 	return rs;
  	 
                         }
  
	                          
 
 public ResultSet getCourses(){
  	
  	String sql="select id,name from course  ";
 
 	sqlBean db = new sqlBean();
  	
ResultSet rs = db.executeQuery(sql);
 
 	return rs;  	        
  
                              }
     
                         
   	public boolean hasLogin(String id){   

  	boolean f=false;
 
   String sql="select id from classes where id ='"+id+"'";
  
	sqlBean db =new sqlBean();
 
 	try{
 
 	ResultSet rs=db.executeQuery(sql);
  
	if(rs.next()){ f=true;}
  
	else{ f=false;}

  	}catch(Exception e){ e.getMessage();}
  
	return f;
  	  
                     }
  	
                                                                              
 
  public String hasMoreclass(String tea_id,String cour_time){   //检查教师是否同一时间上两门课程
 
   
    String temp="";
 
   String sql="select id from classes  "+
  
             "where tea_id='"+tea_id+"' and cour_time='"+cour_time+"'   "; 
 
     sqlBean db =new sqlBean();         	
  
  	try{
 
 	ResultSet rs=db.executeQuery(sql);

  	if(rs.next()){ temp=rs.getString("id");}
  
	else{ temp="no";}
 
 	}catch(Exception e){ System.out.print(e.getMessage());}
 
 	return temp;        
  	
                  }
  	
                  
  	                  
 
 public void addClass(){
  	
	
  	String sql="insert into classes(id,tea_id,cour_id,room_id,cour_time)  "+

  	           "values('"+id+"','"+tea_id+"','"+cour_id+"','"+room_id+"','"+cour_time+"') ";
  
	    try{       
  
		sqlBean db =new sqlBean(); 

  		db.executeInsert(sql);} catch(Exception e){System.out.print(e.toString());}
 
 		}
  
		
  
		

   public void updateClass(String id,String tea_id,String cour_id,

                           String room_id,String cour_time){    	

      String sql="update classes "+

                 " set tea_id='"+tea_id+"',cour_id='"+cour_id+"',"+

                 "room_id='"+room_id+"',cour_time='"+cour_time+"'  "+
 
                " where id='"+id+"' ";

                 sqlBean db= new sqlBean();

                 db.executeInsert(sql);

                 }
 
                

  public void updateClass(String id,String cour_id,

                          String room_id){    	

      String sql="update classes "+

                 " set cour_id='"+cour_id+"',"+

                 "room_id='"+room_id+"' "+

                 " where id='"+id+"' ";

                 sqlBean db= new sqlBean();

                 db.executeInsert(sql);

                 }       
 
                

   public int deleteClass(String id){  

        int num=0; 	

    	String sql="delete  from classes where id ='"+id+"' ";

    	sqlBean db= new sqlBean();

        num=db.executeDelete(sql);
 
       return num;

    	}

    	

   
public ResultSet getClasses(){

   	
   	String sql="select classes.id,tea_id,cour_id,room_id,cour_time, "+

			"course.name as cour_name,teacher.name as tea_name "+

      		"from classes ,course,teacher  "+

     		"where classes.cour_id=course.id "+

    		"and classes.tea_id=teacher.id ";

   			sqlBean db= new sqlBean();

		ResultSet rs = db.executeQuery(sql);

		 return rs;           

   	} 	                                           	

 	   	                 
  

}