subject_question_difficultdao.java

可以实现在线考试

package dao;

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

import vo.Subject_Question_DifficultVO;

public class Subject_Question_DifficultDAO 
{
	private Connection conn = null;
	private Statement state = null;
	private ResultSet rs = null;
	
	//查询全部试题
	public ArrayList findAlls_q_dByCid(int pageSize,int startRows,int cid)
	{
		ArrayList array = new ArrayList();
		conn = Tools.getConnection();
		try {
			state = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
			rs = state.executeQuery("select * from subject,question,difficult where subject.cid=question.cid and question.cid="+cid);
			rs.absolute(startRows);
			for(int i=0;i<pageSize;i++)
			{
				Subject_Question_DifficultVO sqdvo = new Subject_Question_DifficultVO();
				sqdvo.setCid(rs.getInt("cid"));
				sqdvo.setCname(rs.getString("cname"));
				sqdvo.setAnswer(rs.getString("answer"));
				sqdvo.setDid(rs.getInt("did"));
				sqdvo.setDname(rs.getString("dname"));
				sqdvo.setFlag(rs.getString("flag"));
				sqdvo.setQuestion(rs.getString("question"));
				sqdvo.setOptionA(rs.getString("optionA"));
				sqdvo.setOptionB(rs.getString("optionB"));
				sqdvo.setOptionC(rs.getString("optionC"));
				sqdvo.setOptionD(rs.getString("optionD"));
				sqdvo.setQid(rs.getInt("qid"));
				sqdvo.setQscore(rs.getInt("qscore"));
				array.add(sqdvo);
				if(!rs.next())
					break;
			} 
		} 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;
	}
	//返回总行数
	public int ReturnTotalRows()
	{
		int totalRows = 0;
		try {
			conn = Tools.getConnection();
			state= conn.createStatement();
			rs = state.executeQuery("select count(*) con from subject,question,difficult where subject.cid = question.cid");
			if(rs.next())
			{
				totalRows = rs.getInt("con");
			}
			
		} 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 totalRows;
	}
}