Struts自定义标签–使用表格显示数据

emptypagetruefalse

2.DisplayTag.java

package com.test;import java.util.List;import javax.servlet.http.HttpSession;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspTagException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.tagext.TagSupport;import com.test.Hibernate.User;public class DisplayTag extends TagSupport {/****/private static final long serialVersionUID = 1L;private String name = "alluser";private String page;public String getName() {return name;}public void setName(String name) {this.name = name;}public String getPage() {return page;}public void setPage(String page) {this.page = page;}private String test;public String getTest() {return test;}public void setTest(String test) {this.test = test;}@Overridepublic int doStartTag() throws JspException {return SKIP_BODY;}public int doEndTag() throws JspException {boolean valid = false;HttpSession session = pageContext.getSession();if (session != null && session.getAttribute(name) != null) {valid = true;} else {try {pageContext.forward(page);} catch (Exception e) {// TODO: handle exceptionthrow new JspException(e.toString());}}JspWriter ut = pageContext.getOut();try {List users = (List) session.getAttribute("alluser");if (valid) {out.println("");out.println("");out.println("");out.println("");out.println("");out.println("");for (int i = 0; i < users.size(); i++) {User user = (User) users.get(i);out.println("");out.println("");out.println("");out.println("");}out.println("

");} else {out.println("null");}} catch (Exception e) {// TODO Auto-generated catch blockthrow new JspTagException("IOException:" + e.toString());}return SKIP_PAGE;}@Overridepublic void release() {// TODO Auto-generated method stubsuper.release();this.name = "alluser";this.page = "login.jsp";}}

3.LoginAction.java

package com.test.struts.action;import java.util.List;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.struts.action.Action;import org.apache.struts.action.ActionForm;import org.apache.struts.action.ActionForward;import org.apache.struts.action.Actionmapping;import org.apache.struts.validaTor.DynaValidaTorForm;import com.test.Hibernate.UserDAO;public class LoginAction extends Action {private UserDAO userDao;public UserDAO getUserDao() {return userDao;}public void setUserDao(UserDAO userDao) {this.userDao = userDao;}public ActionForward execute(Actionmapping mapping, ActionForm. form, HttpServletRequest request, HttpServletResponse response) throws Exception {DynaValidaTorForm. loginForm. = (DynaValidaTorForm) form;String username = loginForm.getString("username");String password = loginForm.getString("password");if (userDao.isValidUser(username, password)) {List users = userDao.showAll();//在userDao中写操作数据库的方法，其中，showAll()方法是取出数据库中说有数据request.setAttribute("user", username);request.getSession().setAttribute("alluser", users);return mapping.findForward("indexGo");} else {return mapping.getInputForward();}}}

4.使用

...<%@ taglib uri="/WEB-INF/app.tld" prefix="app" %>......

有时我们选择改变，并非经过深思熟虑，