<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" 
    xmlns="http://java.sun.com/xml/ns/j2ee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
  
  <servlet>
        <servlet-name>action</servlet-name>
        <servlet-class>
            org.apache.struts.action.ActionServlet
        </servlet-class>
        <init-param>
            <param-name>config</param-name>
            <param-value>/WEB-INF/struts-config.xml</param-value>
        </init-param>
        <init-param>
            <param-name>debug</param-name>
            <param-value>2</param-value>
        </init-param>
        <init-param>
            <param-name>detail</param-name>
            <param-value>2</param-value>
        </init-param>
        <load-on-startup>2</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>action</servlet-name>
        <url-pattern>*.do</url-pattern>
    </servlet-mapping>
  
</web-app>

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE struts-config PUBLIC
          "-//Apache Software Foundation//DTD Struts Configuration 1.2//EN"
          "http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd">

<struts-config>

<!-- ActionForm  -->
    <form-beans>
    <!-- name:名称 type:类路径 -->
        <form-bean name="loginForm" type="com.trustview.form.LoginForm">
        </form-bean>
    </form-beans>
<!-- 设置全局URL，必须写在Action前面，这样任何Action都可以使用 -->
    <global-forwards>
        <forward name="result" path="/result.jsp" />
    </global-forwards>

<!-- 注册Action -->
    <action-mappings>
    <!-- name：名称 type：类路径 path：客户端（JSP）提交到服务器端时指定的路径（Form表单中的action=”/login.do" -->
        <action path="/login" type="com.trustview.action.Login"
            name="loginForm" scope="request">
            <!-- 局部URL，只有这个action可以使用 -->
            <forward name="success" path="/success.jsp"></forward>
            <forward name="error" path="/error.jsp"></forward>
        </action>
    </action-mappings>


</struts-config>

package com.trustview.action;
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 com.trustview.form.LoginForm;

public class Login extends Action {

    @Override
    public ActionForward execute(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        LoginForm lf = (LoginForm) form;
        String username = lf.getUsername();
        String password = lf.getPassword();
        String errorInfo = "";
        String result = login(username, password);
        if (result.equals("success")) {
            request.setAttribute("username", username);
            return mapping.findForward("success");
        } else if (result.equals("username")) {
            errorInfo = "密码错误";
        } else {
            errorInfo = "用户名错误";
        }
        request.setAttribute("errorInfo", errorInfo);
        return mapping.findForward("error");
    }

    private String login(String username, String password) {
        if("admin".equals(username)&&"admin".equals(password)){
            return "success";
        }else if(!"admin".equals(username)){
            return "password";
        }
        
        return "username";
    }

}

package com.trustview.form;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;

    public class LoginForm extends ActionForm {

        private String username;
        private String password;

        public void reset(ActionMapping mapping, HttpServletRequest request) {
            System.out.println("--------reset()-------------");
            super.reset(mapping, request);
        }

        public ActionErrors validate(ActionMapping mapping,
                HttpServletRequest request) {
            System.out.println("--------validate()-------------");
            return super.validate(mapping, request);
        }

        public String getUsername() {
            return username;
        }

        public void setUsername(String username) {
            this.username = username;
        }

        public String getPassword() {
            return password;
        }

        public void setPassword(String password) {
            this.password = password;
        }

    }

<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
请输入用户名密码
    <head>
        <title>首页</title>
    </head>

    <body>
        <html:form action="/login.do">
            用户名：<html:text property="username"></html:text><br/>
            密码: <html:password property="password"></html:password><br/>
            <html:submit>提交</html:submit>
        </html:form>
    </body>
</html>