1.*号通配符优化struts.xml代码
创建一个UserAction的动作类
package action; import com.opensymphony.xwork2.ActionSupport; public class UserAction extends ActionSupport{ //添加用户 public String add(){ return SUCCESS; } //删除用户 public String delete(){ return SUCCESS; } //更新用户 public String update(){ return SUCCESS; } //查找用户 public String find(){ return SUCCESS; } }
Struts.xml文件配置
<!--第一种配置方式--> <!--<package name="p2" extends="struts-default"> <action name="add" class="action.UserAction" method="add"> <result name="success">/add.jsp</result> </action> <action name="delete" class="action.UserAction" method="delete"> <result name="success">/delete.jsp</result> </action> <action name="find" class="action.UserAction" method="find"> <result name="success">/find.jsp</result> </action> <action name="update" class="action.UserAction" method="update"> <result name="success">/update.jsp</result> </action> </package>--> <!--采用通配符的方式--> <!-- 动作访问之通配符 * ：这里是一个*--> <package name="p2" extends="struts-default"> <action name="*" class="action.UserAction" method="{1}"> <result name="success">/{1}.jsp</result> </action> </package>
2.Struts.xml配置文件中的result元素的type取值的四种类型
chain的配置实例：
<1>利用chain转发到同一个包下的不同action
<package name="p3" extends="struts-default"> <action name="hello1" class="action.HelloAction" method="sayHello"> <result name="success" type="chain">hello2</result> </action> <action name="hello2" class="action.HelloAction2" method="sayHello2"> <result name="success">/hello2.jsp</result> </action> </package>
效果图：
<2>利用chain转发到不同包下的不同action
<package name="p3" extends="struts-default"> <action name="hello1" class="action.HelloAction" method="sayHello"> <result name="success" type="chain">hello3</result> </action> <action name="hello2" class="action.HelloAction2" method="sayHello2"> <result name="success">/hello2.jsp</result> </action> </package> <package name="p4" extends="struts-default"> <action name="hello3" class="action.HelloAction3" method="sayHello3"> <result name="success">/hello3.jsp</result> </action> </package>
注意：若加上namespace属性,则struts.xml文件的配置应修改为：
<package name="p3" extends="struts-default" namespace="/n3"> <action name="hello1" class="action.HelloAction" method="sayHello"> <result name="success" type="chain"> <param name="namespace">/n4</param> <param name="actionName">hello3</param> </result> </action> <action name="hello2" class="action.HelloAction2" method="sayHello2"> <result name="success">/hello2.jsp</result> </action> </package> <package name="p4" extends="struts-default" namespace="/n4"> <action name="hello3" class="action.HelloAction3" method="sayHello3"> <result name="success">/hello3.jsp</result> </action> </package>
效果图：
3.动作类中的servlet api访问
通过ServletActionContext获取获取servlet 的api
package action; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; public class TestAction extends ActionSupport{ public String test(){ //获取servlet 的api方式 //第一种方式：通过ServletActionContext //1.response HttpServletResponse response = ServletActionContext.getResponse(); //2.request HttpServletRequest request = ServletActionContext.getRequest(); //3.session HttpSession session = request.getSession(); //4.application【ServletContext】 ServletContext application = ServletActionContext.getServletContext(); //NONE不跳转，也就是不用找result标签 return NONE; } }
4.Action接收请求参数的方式
(1)通过request对象
//获取请求参数 //第一种方法：通过request对象 HttpServletRequest request = ServletActionContext.getRequest(); String username = request.getParameter("username"); String password = request.getParameter("password"); System.out.println(username); System.out.println(password);
(2)第2种方式：通过属性的set注入
package action; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import javax.xml.ws.RequestWrapper; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; public class LoginAction extends ActionSupport{ private String username; private String password; public void setUsername(String username) { System.out.println("setUsername"); this.username = username; } public void setPassword(String password) { System.out.println("setPassword"); this.password = password; } public String login(){ //获取请求参数 /*//第一种方法：通过request对象 HttpServletRequest request = ServletActionContext.getRequest(); String username = request.getParameter("username"); String password = request.getParameter("password");*/ System.out.println(username); System.out.println(password); //第二种方式：通过属性的set注入 //NONE不跳转，也就是不用找result标签 return NONE; } }
(3)第3种方式:通过模型驱动(最常用)
创建一个model---->User
package model; public class User { 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; } @Override public String toString() { return "User [username=" + username + ", password=" + password + "]"; } }
动作类代码：
package action; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; import javax.xml.ws.RequestWrapper; import com.opensymphony.xwork2.ModelDriven; import model.User; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; public class LoginAction extends ActionSupport implements ModelDriven<User> { private User user = new User(); @Override public User getModel() { // TODO Auto-generated method stub return user; } public String login(){ //获取请求参数 /** * 第三种方式: 通过模型驱动【最常用】 * 实现步骤： * 1.在action里实现一个模型驱动接口 * 2.提供一个模型属性，并一定要赋值 * 通过这种方式，在jsp页面中就不用写user. * * 这是模型驱动的原理是因为有个模型驱动的拦截器在处理 * 这个类就com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor */ System.out.println(user); //NONE不跳转，也就是不用找result标签 return NONE; } }
控制台输出：
