optionalscoredao.java

学生信息管理系统

package dao;
import java.sql.*;
import conn.ConnectDB;
import java.util.*;
import vo.OptionalScoreVO;
public class OptionalScoreDAO 
{
	public OptionalScoreDAO()
	{
		
	}
	public boolean checkScore(String student_id,String term,String course_id)
	{
		boolean isexist=false;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			ResultSet rs=stat.executeQuery("select * from optional_score where student_id='"+student_id+"'and term='"+term+"'and course_id='"+course_id+"'");
			if(rs.next())
			{
				isexist=true;
			}
			else
			isexist=false;
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return isexist;
	}
	public boolean checkStudent(String student_id)
	{
		boolean isexist=false;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			ResultSet rs=stat.executeQuery("select * from optional_score where student_id='"+student_id+"'");
			if(rs.next())
			{
				isexist=true;
			}
			else
			isexist=false;
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return isexist;
	}
	public OptionalScoreVO getScoreByStudentId(String student_id,String term,String course_id)
	{
		OptionalScoreVO scorevo=null;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			ResultSet rs=stat.executeQuery("select * from optional_score where student_id='"+student_id+"'and term='"+term+"'and course_id='"+course_id+"'");
			if(rs.next())
			{
				scorevo=new OptionalScoreVO();
				scorevo.setStudentId(rs.getString("student_id"));
				scorevo.setCourseId(rs.getString("course_id"));
				scorevo.setExamtime(rs.getString("datetimes"));
				scorevo.setGrade(rs.getString("grade"));
				scorevo.setTerm(rs.getString("term"));
				scorevo.setNote(rs.getString("note"));
			}
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return scorevo;
	}
	public ArrayList getScoresByStudentId(String student_id,String term)
	{
		ArrayList scores=new ArrayList();
		OptionalScoreVO scorevo=null;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			ResultSet rs=stat.executeQuery("select * from optional_score where student_id='"+student_id+"'and term='"+term+"'");
			while(rs.next())
			{
				scorevo=new OptionalScoreVO();
				scorevo.setStudentId(rs.getString("student_id"));
				scorevo.setCourseId(rs.getString("course_id"));
				scorevo.setExamtime(rs.getString("datetimes"));
				scorevo.setGrade(rs.getString("grade"));
				scorevo.setTerm(rs.getString("term"));
				scorevo.setNote(rs.getString("note"));
				scores.add(scorevo);
			}
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return scores;
	}
	public void insertScore(OptionalScoreVO scorevo)
	{
		try
		{
			ConnectDB.executeUpdate("insert into optional_score values('"+scorevo.getStudentId()+"','"+scorevo.getCourseId()+"','"+scorevo.getTerm()+"','"+scorevo.getGrade()+"','"+scorevo.getNote()+"','"+scorevo.getExamtime()+"')");
			
		}
			catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	public void alterScore(OptionalScoreVO scorevo)
	{
		ResultSet rs=null;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from optional_score where student_id='"+scorevo.getStudentId()+"'and term='"+scorevo.getTerm()+"'and course_id='"+scorevo.getCourseId()+"'");
			if(rs.next())
			{
				ConnectDB.executeUpdate("update optional_score set score='"+scorevo.getGrade()+"',datetimes='"+scorevo.getExamtime()+"',note='"+scorevo.getNote()+"'where student_id='"+scorevo.getStudentId()+"'and term='"+scorevo.getTerm()+"'and course_id='"+scorevo.getCourseId()+"'");
				
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
	public void deleteScore(String student_id,String term,String course_id)
	{
		ResultSet rs=null;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from optional_score where student_id='"+student_id+"'and term='"+term+"'and course_id='"+course_id+"'");
			if(rs.next())
			{
				ConnectDB.executeUpdate("delete from optional_score where student_id='"+student_id+"'and term='"+term+"'and course_id='"+course_id+"'");
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}