coursedao.java

学生信息管理系统

package dao;
import conn.ConnectDB;
import java.util.*;
import java.sql.*;
import vo.*;
public class CourseDAO
{
	public CourseDAO()
	{
		
	}
	public boolean checkCourse(String course_id,String term)
	{
		ResultSet rs=null;
		boolean isexist=false;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from course where course_id='"+course_id+"'and term='"+term+"'");
			if(rs.next())
			{
				isexist=true;
			}
			else
			isexist=false;
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
			
			return isexist;
	}
	public CourseVO getCourseByIdAndTerm(String course_id,String term)
	{
		ResultSet rs=null;
		CourseVO coursevo=null;
		try
		{
			Connection  conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from course where course_id='"+course_id+"'and term='"+term+"'");
			if(rs.next())
			{
				coursevo=new CourseVO();
				coursevo.setCourseId(course_id);
				coursevo.setTerm(term);
				coursevo.setCourseName(rs.getString("coursename"));
				coursevo.setExamtype(rs.getString("examtype"));
				coursevo.setScore(rs.getString("score"));
				coursevo.setTotal(rs.getString("total"));
				
			}
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return coursevo;
	}
	public ArrayList getCourseByTerm (String term)
	{
		ResultSet rs=null;
		ArrayList courses=null;
		try
		{
			courses=new ArrayList();
			Connection  conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from course where  term='"+term+"'");
			while(rs.next())
			{
				
				CourseVO coursevo=new CourseVO();
				coursevo.setCourseId(rs.getString("course_id"));
				coursevo.setTerm(rs.getString("term"));
				coursevo.setCourseName(rs.getString("coursename"));
				coursevo.setExamtype(rs.getString("examtype"));
				coursevo.setScore(rs.getString("score"));
				coursevo.setTotal(rs.getString("total"));
				courses.add(coursevo);
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return courses;
	}
	public void insertCourse(CourseVO coursevo)
	{
		try
		{
			ConnectDB.executeUpdate("insert into course values('"+coursevo.getCourseId()+"','"+coursevo.getCourseName()+"','"+coursevo.getTerm()+"','"+coursevo.getExamtype()+"','"+coursevo.getTotal()+"','"+coursevo.getScore()+"')");
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	public void updateCourse(CourseVO coursevo)
	{
		ResultSet rs=null;
		try
		{
			Connection  conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from course where course_id='"+coursevo.getCourseId()+"'");
			if(rs.next())
			{
				ConnectDB.executeUpdate("update course set coursename='"+coursevo.getCourseName()+"',examtype='"+coursevo.getExamtype()+"',term='"+coursevo.getTerm()+"',total='"+coursevo.getTotal()+"',score='"+coursevo.getScore()+"'where course_id='"+coursevo.getCourseId()+"'");
				
			}
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	public void deleteCourse(String course_id)
	{
		ResultSet rs=null;
		try
		{
			Connection  conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from course where course_id='"+course_id+"'");
			if(rs.next())
			{
				ConnectDB.executeUpdate("delete from exam where course_id='"+course_id+"'");
				ConnectDB.executeUpdate("delete from compulsory_score where course_id='"+course_id+"'");
				ConnectDB.executeUpdate("delete from teacher_class_course where course_id='"+course_id+"'");
				ConnectDB.executeUpdate("delete from course where course_id='"+course_id+"'");
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}