搭建一个strust1环境

Struts是apache一个基于MVC 模式的web应用开源框架，它是一个基于请求驱动的MVC模式。利用Strust开源框架，能提高web开发效率，使用少量代码就可以达到servlet中一些复杂的操作，它对serlvet进行了封装。

搭建Struts开发环境需主要有如下几部:

1.导入struts相关jar包，主要的jar包有(以1.3.8为例)

2.配置web.xml，主要是用来配置哪些请求处理有struts的actionServlet来处理。

  <servlet>
  	<servlet-name>ActionServlet</servlet-name>  <!-- struts处理的请求的action,由struts编写，不需开发者编写 -->
  	<servlet-class>org.apache.struts.action.ActionServlet</servlet-class><!--actionServlet类 -->
  	 <init-param>
      		<param-name>config</param-name>
      		<param-value>/WEB-INF/struts-config.xml</param-value><!--配如何处理每个action -->
    	</init-param>
   	 <load-on-startup>2</load-on-startup> <!-- 指定web应用启动时加载此actionServlet -->
  	
  </servlet>
  
  <servlet-mapping>  
  	<servlet-name>ActionServlet</servlet-name>
  	<url-pattern>*.do</url-pattern><!--指定所有.do请求都有struts来处理  -->
  </servlet-mapping>

3.actionServlet是struts的中央处理器，所有请求都将转发到actionServlet，actionServlet将会调用每个具体的action,至于调用哪个action，将会在struts-config.xml中进行配置，此配置默认放在WEB-INF目录下。

<struts-config>
	<form-beans>
		<form-bean name="UserFormBean" type="cn.itcast.web.formbean.UserFormbean"></form-bean>
	</form-beans>

	<!-- 配置struts收到请求后找一个action处理 -->
	<!-- path指的是对应的action,即web页面输入的Register.do，它将找type对应的action类来处理，name指定FormBean,它将会把请求消息的参数封装到一个bean对象中，此bean对应form-beans标签中的type指定的bean-->
	<action-mappings>
		<action path="/Register" type="cn.itcast.web.action.RegisterAction" name="UserFormBean"></action>
	</action-mappings>

</struts-config>

Stuts执行流程图如下所示:

开发者编写的Action需要实现Action接口，相关开发代码在此接口的exectue方法中执行，此方法最终返回一个actionForwad对象，此对象封装了要跳转的页面。图中的Action

下面是上例代码：

//UserFormBean

public class UserFormbean extends ActionForm {

	private String username;
	private String password;
	private String email;
	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;
	}
	public String getEmail() {
		return email;
	}
	public void setEmail(String email) {
		this.email = email;
	}	
}

//负责执行的Register的RegisterAction

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 cn.itcast.web.formbean.UserFormbean;

public class RegisterAction extends Action {

	@Override
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		
		
		UserFormbean bean = (UserFormbean) form;
		System.out.println(bean.getUsername());
		System.out.println(bean.getPassword());
		System.out.println(bean.getEmail());
		
		
		try{
			System.out.println("向数据注册用户！！");
			request.setAttribute("message", "注册成功");
			
		
		}catch (Exception e) {
			request.setAttribute("message", "注册失败");
			
		}
		
		return mapping.findForward("message");
	}	
}

web.xml配置文件

<?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">
  
  <servlet>
  	<servlet-name>ActionServlet</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>
    <load-on-startup>2</load-on-startup>
  	
  </servlet>
  
  <servlet-mapping>
  	<servlet-name>ActionServlet</servlet-name>
  	<url-pattern>*.do</url-pattern>
  </servlet-mapping>
  
  
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

struts-config.xml配置文件

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

<!DOCTYPE struts-config PUBLIC
          "-//Apache Software Foundation//DTD Struts Configuration 1.3//EN"
          "http://struts.apache.org/dtds/struts-config_1_3.dtd">

<struts-config>
	<form-beans>
		<form-bean name="UserFormBean" type="cn.itcast.web.formbean.UserFormbean"></form-bean>
			
	</form-beans>

	<!-- 配置struts收到请求后找一个action处理 -->

	<action-mappings>
		<action path="/Register" type="cn.itcast.web.action.RegisterAction" name="UserFormBean"></action>
		
               <forward name="message" path="/message.jsp"></forward>

	</action-mappings>

</struts-config>