questiondao.java

可以实现在线考试

package dao;

import java.sql.*;
import java.util.ArrayList;

import po.QuestionPO;

public class QuestionDAO 
{
	private Connection conn = null;
	private Statement state = null;
	private ResultSet rs = null;
	
	//根据科目ID查出全部试题
	public ArrayList findByCid(int cid)
	{
		ArrayList array = new ArrayList();
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			rs = state.executeQuery("select * from question where cid="+cid);
			while(rs.next())
			{
				QuestionPO qpo = new QuestionPO();
				qpo.setCid(rs.getInt("cid"));
				qpo.setAnswer(rs.getString("answer"));
				qpo.setDid(rs.getInt("did"));
				qpo.setQuestion(rs.getString("question"));
				qpo.setOptionA(rs.getString("optionA"));
				qpo.setOptionB(rs.getString("optionB"));
				qpo.setOptionC(rs.getString("optionC"));
				qpo.setOptionD(rs.getString("optionD"));
				qpo.setQscore(rs.getInt("qscore"));
				array.add(qpo);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(rs != null)
				rs.close();
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return array;
	}
	
	//根据问题ID查找
	public QuestionPO findByQid(int qid)
	{
		QuestionPO qpo = null;
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			rs = state.executeQuery("select * from question where qid="+qid);
			while(rs.next())
			{
				qpo = new QuestionPO();
				qpo.setCid(rs.getInt("cid"));
				qpo.setAnswer(rs.getString("answer"));
				qpo.setDid(rs.getInt("did"));
				qpo.setQuestion(rs.getString("question"));
				qpo.setOptionA(rs.getString("optionA"));
				qpo.setOptionB(rs.getString("optionB"));
				qpo.setOptionC(rs.getString("optionC"));
				qpo.setOptionD(rs.getString("optionD"));
				qpo.setQscore(rs.getInt("qscore"));
				qpo.setChoose(rs.getString("choose"));
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(rs != null)
				rs.close();
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return qpo;
	}
	
	//取问题ID
	public int  getNextQuestionID()
	{
		int myID = 0;
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			rs = state.executeQuery("select max(qid) qid from question");
			if(rs.next())
			{
				myID = rs.getInt("qid");
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(rs != null)
				rs.close();
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return ++myID;
	}
	
	//添加问题记录
	public boolean addQuestion(QuestionPO question)
	{
		boolean isok = false;
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			int i = state.executeUpdate("insert into question values("+question.getQid()+","+question.getCid()+",'"+question.getQuestion()+"','"+question.getOptionA()+"','"+question.getOptionB()+"','"+question.getOptionC()+"','"+question.getOptionD()+"','"+question.getAnswer()+"',"+question.getDid()+","+question.getQscore()+")");
			if(i > 0)
			{
				isok = true;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return isok;
	}
	
	//修改问题记录
	public boolean updateQuestion(QuestionPO question)
	{
		boolean isok = false;
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			int i = state.executeUpdate("update question set cid="+question.getCid()+",question ='"+question.getQuestion()+"',optionA ='"+question.getOptionA()+"',optionB ='"+question.getOptionB()+"',optionC ='"+question.getOptionC()+"',optionD ='"+question.getOptionD()+"',answer ='"+question.getAnswer()+"',did ="+question.getDid()+",qscore ="+question.getQscore()+" where qid="+question.getQid());
			if(i > 0)
			{
				isok = true;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return isok;
	}
	
	//删除问题记录
	public boolean deleteQuestion(int qid)
	{
		boolean isok = false;
		conn = Tools.getConnection();
		try {
			state = conn.createStatement();
			int i = state.executeUpdate("delete from question where qid="+qid);
			if(i > 0)
			{
				isok = true;
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			try {
				if(state != null)
				state.close();
				if(conn != null)
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		return isok;
	}
}