truts1入门实例（简单登录）

原文地址：http://www.cnblogs.com/wangchenyang/archive/2011/09/19/2181893.html

现在开始加入公司的核心项目，但由于项目开发比较早，所以使用的技术不是很新潮，前台用的还是struts1。

虽然不是什么新技术，但仍可以从中学到好多东西的。花了一个晚上的时间终于把struts1的流程跑通了。

省略了创建过程及加入jar包的过程，直接进入正题。

首页要在web.xml中添加相应的struts配置：

<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>

然后在config所对应的目录下添加struts配置文件struts-config.xml

<?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.login.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.login.LoginAction"            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>

注：Action和Form的关系是一个Action只能对应一个Form（通过Action的name属性）

而一个Form可以被多个Action调用

LoginAction.java

package com.login;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;public class LoginAction 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 = UserManager.getInstance().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");    }}

LoginForm.java

package com.login;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;    }}

对我个人来说最重要的是前台jsp页面没有掌握，经常在页面上花费很多时间

在编写JSP页面时要用struts标签，而我经常会忘记

引入jsp标签

<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %><%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>

index.jsp

<%@ 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><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>submit</html:submit></html:form></body></html>

 

展示结果（将Action的返回值展示到JSP页面上）

<%@ 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><head><title>Error</title></head><body><bean:write name="errorInfo" scope="request" /></body></html>