selectcourseservlet.java

我实习时候的设计

package cn.yxh.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import cn.yxh.dao.CourseDAO;

public class selectCourseServlet extends HttpServlet {

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		doPost(request,response);
	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		String studentid = (String)request.getSession().getAttribute("studentid");
		String courseid = request.getParameter("courseid");
		
		System.out.println(studentid+" "+courseid);
		
		boolean a = CourseDAO.checkSelectCourse(studentid, courseid);
		System.out.println("是否重复选课"+a);
		if(a) {
			request.setAttribute("already", "您已经选择过该课程了");
			request.getRequestDispatcher("alreadyselect.jsp").forward(request, response);
		}
		else{
			boolean b = CourseDAO.selectCourse(studentid, courseid);
			
			if(b) {
				request.getRequestDispatcher("SignalCourseInfoServlet").forward(request, response);
			}
		}
		
	}

}