具体分析Struts工作流程

         1.Webclient提交数据到Tomcat，在form表单中需说明表单提交的action是*.do或*.action,mothod是post或get；

    2.Tomcat接收Webclient提交的表单。将表单数据打包到HttpServletRequest和HttpServletResponse对象中。然后通过doPost或doGet方式把request、response提交到ActionServlet(ActionServlet是Struts内部封装好的)；

    要使用Struts封装的ActionServlet，须要在web.xml中配置ActionServlet，配置信息例如以下：

	<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>


	<!-- Standard Action Servlet Mapping -->
	<servlet-mapping>
		<servlet-name>action</servlet-name>
		<url-pattern>*.do</url-pattern>
	</servlet-mapping>

   3.ActionServlet是struts的中央控制器。它任务例如以下：

    (1)它负责截取Webclient提交的URL。比方login.jsp的action是login.do，然后依据URL从struts-config.xml中获得配置信息。配置信息须要手动在struts-config.xml中配置。配置信息例如以下：

	<action-mappings>
		<action path="/login" type="com.tgb.struts.LoginAction" name="loginForm"
			scope="request">
			<forward name="success" path="/login_success.jsp"></forward>
			<forward name="error" path="/login_error.jsp"></forward>
		</action>
	</action-mappings>

    (2)创建ActionForm类的对象，用于收集表单数据，ActionForm类代码例如以下：

package com.tgb.struts;

import org.apache.struts.action.ActionForm;

/**
 * 登录ActionForm，负责表单收集数据
 * 表单的属性必须和ActionForm中的get、set属性一致
 * @author quwenzhe
 * 
 */

public class LoginActionForm extends ActionForm {
	private String username;
	private String password;

	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;
	}

}

	<form-beans>
		<form-bean name="loginForm" type="com.tgb.struts.LoginActionForm" />
	</form-beans>

package com.tgb.struts;

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;

/**
 * 登录Action 负责获得表单数据，调用业务逻辑。返回转向视图
 * 
 * @author quwenzhe
 * 
 */
public class LoginAction extends Action {

	@Override
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		LoginActionForm laf = (LoginActionForm) form;
		String username = laf.getUsername();
		String password = laf.getPassword();

		if ("admin".equals(username) && "admin".equals(password)) {
			// 登录成功
			return mapping.findForward("success");
		} else {
			// 登录失败
			return mapping.findForward("error");
		}
	}

}