addlessonservlet.java

基于MVC模式的学生选课系统。实现学生信息注册、学生选课和管理员的课程信息维护操作

package servlet;

import dao.DataAccess;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class AddLessonServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public AddLessonServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * 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 {

		response.setCharacterEncoding("gb2312");
		request.setCharacterEncoding("gb2312");
		RequestDispatcher dispatcher = null;
		String lessonId = request.getParameter("Lid");
		String lessonName = request.getParameter("Lname");
		try{
				if(lessonId==null||lessonName.equals("")) throw new Exception("lessonId或lessonName为空");
				
				DataAccess dataInsert = new DataAccess();
				dataInsert.insertLesson(lessonId, lessonName);
				request.setAttribute("message","您以已经成功建立了名称为"+lessonName+"的课程");
				dispatcher = request.getRequestDispatcher("/thanks.jsp");
			
		} catch(Exception e){
			request.setAttribute("failMessage","无法建立该课程，请重试");
			dispatcher = request.getRequestDispatcher("/error.jsp");
			
		}
		dispatcher.forward(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 {

		doGet(request,response);
	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occure
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}