messagehandleservlet.java

简单的流言板系统,用myeclipse进行编写的,采用简单的jstl+javabean+servlet+jsp,属于三层架构.

package me.work.servlets;

import java.io.IOException;
import java.sql.SQLException;
import java.util.List;

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

import me.work.beans.MessageBean;
import me.work.services.DBOperation;

public class MessageHandleServlet extends HttpServlet {

	/**
	 * serialVersionUID
	 */
	private static final long serialVersionUID = 1L;

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {

		doPost(req, resp);
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// get the paramter method
		String method = req.getParameter("method");
		// add message
		if ("a".equals(method)) {
			String title = req.getParameter("title");
			String content = req.getParameter("content");
			if ("".equals(title) || "".equals(content)) {
				req
						.setAttribute("error",
								"Add failed ,please make sure you filled all the blanks");
				req.getRequestDispatcher("./pages/addNew.jsp").forward(req,
						resp);
				return;
			}
			MessageBean msg = new MessageBean();
			msg.setMsgTitle(title);
			msg.setMsgContent(content);

			DBOperation dbo = new DBOperation();
			try {
				if (dbo.addMessage(msg, req.getSession().getAttribute(
						"userName").toString())) {
					req.setAttribute("added", "Add successfully");
					req.getRequestDispatcher("./pages/addNew.jsp").forward(req,
							resp);

				} else {
					req
							.setAttribute("error",
									"Add failed ,please make sure you filled all the blanks");
					req.getRequestDispatcher("./pages/addNew.jsp").forward(req,
							resp);

				}
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		} else if ("delete".equals(method)) {
			// delete user message
			String msgid = req.getParameter("id");
			if (msgid == null || "".equals(msgid)) {
				return;
			}
			DBOperation dbo = new DBOperation();
			// do delete
			try {
				if (dbo.deleteMsgByID(Integer.valueOf(msgid).intValue())) {
					req.getRequestDispatcher("/User?method=mmm").forward(req,
							resp);
				}
			} catch (NumberFormatException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (ClassNotFoundException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

		} else if ("check".equals(method)) {
			// check user's message
			String msgID = req.getParameter("id");
			if (msgID == null || "".equals(msgID)) {
				return;
			}
			DBOperation dbo = new DBOperation();
			try {
				List replyList;

				replyList = dbo.getReplyListOfSpecifiedMessage(Integer
						.valueOf(msgID));

				MessageBean msg = dbo.getMessageByID(Integer.valueOf(msgID));
				req.setAttribute("replyList", replyList);
				req.setAttribute("msg", msg);
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

			req.setAttribute("check", "yes");
			req.getRequestDispatcher("./pages/manageMsg.jsp")
					.forward(req, resp);
		}
	}

}