哪个网站做图片外链,网站如何做友情链接,鹤壁网站推广,制作灯笼的材料和做法我用login.jsp进行登录留言板的管理页面用一个servlet进行身份验证。成功-----通过request.getRequestDispatcher(/admin/secure/manage?qlist).forward(request, response);return;其中/admin/secure/manage是ManageServlet的映射路径。来登录到manage的管理…我用login.jsp进行登录留言板的管理页面用一个servlet进行身份验证。成功-----通过request.getRequestDispatcher(/admin/secure/manage?qlist).forward(request, response);return;其中/admin/secure/manage是ManageServlet的映射路径。来登录到manage的管理程序中也就是ManageServlet来执行qlist的操作。然后转向到list.jsp中。------------------------------------------------------------------------------------------------------ManageServlet的代码是package com.v512.servlet;import java.io.IOException;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.dbutils.handlers.BeanListHandler;import com.v512.Guestbook;import com.v512.dbutil.OracleUtil;public class ManageServlet extends HttpServlet {private static final long serialVersionUID -7850908097407733668L;public void update(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String sql update guestbook set name?,email?,phone?,title?,content? where id?;String message ;String param[] { request.getParameter(name),request.getParameter(email), request.getParameter(phone),request.getParameter(title), request.getParameter(content),request.getParameter(id) };OracleUtil db new OracleUtil(java:/comp/env/jdbc/oracleds);db.init();int i db.update(sql, param);if (i 1) {message 更新成功;request.setAttribute(guestbook.admin.update.message, message);request.getRequestDispatcher(/admin/secure/list.jsp).forward(request, response);Guestbook gb new Guestbook();gb.setName(request.getParameter(name));gb.setEmail(request.getParameter(email));gb.setPhone(request.getParameter(phone));gb.setTitle(request.getParameter(title));gb.setContent(request.getParameter(content));request.setAttribute(admin/secure/update, gb);} else {message 更新不成功;request.setAttribute(guestbook.admin.update.message, message);request.getRequestDispatcher(/admin/secure/update.jsp).forward(request, response);}}public void delete(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String sql delete from guestbook where id?;String message ;String[] param { request.getParameter(id) };OracleUtil db new OracleUtil(java:/comp/env/jdbc/oracleds);db.init();int i db.update(sql, param);if (i 1) {message 删除成功;request.setAttribute(guestbook.admindelete.message, message);request.getRequestDispatcher(/admin/secure/delete.jsp).forward(request, response);} else {message 删除不成功;request.setAttribute(guestbook.admin.delete.message, message);request.getRequestDispatcher(/admin/secure/delete.jsp).forward(request, response);}}public void edit(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String sql select * from guestbook where id?;String[] param { request.getParameter(id) };OracleUtil db new OracleUtil(java:/comp/env/jdbc/oracleds);db.init();List list (List) db.query(sql, param, new BeanListHandler(Guestbook.class));request.setAttribute(guestbook.admin.edit, list.get(0));request.getRequestDispatcher(http://www.v512.com).forward(request,response);}public void list(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String sql select id ,name,title from guestbook order by id desc;OracleUtil db new OracleUtil(java:/comp/env/jdbc/oracleds);db.init();List list (List) db.query(sql, null, new BeanListHandler(Guestbook.class));request.setAttribute(guestbook.admin.list, list);request.getRequestDispatcher(/admin/secure/list.jsp).forward(request,response);return;}public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String method request.getParameter(q);if (method.equals(null)) {method list;}if (method.equals(edit)) {edit(request, response);} else if (method.equals(delete)) {delete(request, response);} else if (method.equals(update)) {update(request, response);} else {list(request, response);}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}} ---------------------------------------------------------------------------------可是我的前二次转向已经成功了就是由request.getRequestDispatcher(/admin/secure/manage?qlist).forward(request, response);return; //这行代码的执行是以身份通过为前提的。其中/admin/secure/manage是ManageServlet的映射路径。request.getRequestDispatcher(/admin/secure/list.jsp).forward(request, response);return;然后它可以成功的转向到list.jsp;在list.jsp中又有两个链接如下编辑删除当点击“编辑”或“删除”时就出现了下面的异常java.lang.IllegalStateException: Cannot forward after response has been committedcom.v512.servlet.ManageServlet.edit(ManageServlet.java:73)
