startcommand.java

北大青鸟在线考试系统,包括在线考试模块,教师管理模块,系统管理模块

/*
 * 模型之进入考试业务操作组件
 */
package TestClass;

import javax.servlet.*;
import java.io.*;
import java.sql.*;
import java.util.*;

public class StartCommand implements Command
{
	private String NextPage=null;
	public StartCommand(String nextPage)
	{
		//在构造时定义下一页面
		this.NextPage=nextPage;
	}
	public String execute(ServletRequest request,ServletResponse response)
	{
		//取出传来的参数信息
		String attID=request.getParameter("attNo");
	    //定义随机数
	    int temp=0;
	    int id=0;				
		//实例状态组件
		SubjectBean bean=new SubjectBean();
		//实例数据操作组件
		SubjectDBbean dbBean=new SubjectDBbean();
		try{
			//取试题编号
			ResultSet Rs=dbBean.executeQuery("SELECT SubID FROM Subject");
			while(Rs.next())
			{
				id=Rs.getInt(1);	
		    	//产生随机数
				temp =(new Double(Math.random()*997)).intValue();
				//更新出题顺序
				dbBean.executeUpdate("Update Subject set OutID="+temp+" Where SubID="+id);
			}
			ResultSet Rs1=dbBean.executeQuery("SELECT * FROM Subject INNER JOIN ExToSub on Subject.SubID=ExToSub.SubID Where ExToSub.ExNo='ACCPno001' Order by OutID");
			/*
			 *request.setAttribute传送有问题,
			 *Test.jsp页面用: ResultSet Rs=(ResultSet)request.getAttribute("AllList");接收不到
			 */
			request.setAttribute("TestSub",Rs1);
//			request.setAttribute("AllList",dbBean.GetAllData());
		}
		catch(Exception e){
			System.out.println("StartCommand: "+e);
		}
		dbBean.Close();
		return NextPage;
	}
}