Struts2是一个基于MVC设计模式的Web应用框架，它本质上相当于一个servlet，在MVC设计模式中，Struts2作为控制器(Controller)来建立模型与视图的数据交互。

struts的初步使用

1、创建一个maven项目

1.1Java代码

1.1.1 User.java

 package com.yuan.entity;

 public class User {

     private String uid;

     private String uname;

     public String getUid() {

         return uid;

     }

     public void setUid(String uid) {

         this.uid = uid;

     }

     public String getUname() {

         return uname;

     }

     public void setUname(String uname) {

         this.uname = uname;

     }

     @Override

     public String toString() {

         return "User [uid=" + uid + ", uname=" + uname + "]";

     }

     public User(String uid, String uname) {

         super();

         this.uid = uid;

         this.uname = uname;

     }

     public User() {

         super();

         // TODO Auto-generated constructor stub

     }

 }

1.1.2 HelloAction.java

package com.yuan.web;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import org.apache.struts2.interceptor.RequestAware;

import org.apache.struts2.interceptor.ServletRequestAware;

import org.apache.struts2.interceptor.ServletResponseAware;

import com.opensymphony.xwork2.ActionContext;

import com.opensymphony.xwork2.ModelDriven;

import com.yuan.entity.User;

/**

 * 1.动态调用方法（mvc不具备的优势）

 * 2.struts中的传参

 *  1、set传参

 *  2、参数名.属性名传参

 *  3、实现modeldriven接口传参

 *

 * 3.struts与tomcat的交互

 *   如何将后台的值传到前台去

 *   1、通过request传值

 *   2、值栈传值（get方法传值）

 * @author **

 *

 */

public class HelloAction implements ModelDriven<User>,ServletRequestAware,ServletResponseAware {

    private HttpServletResponse response;

    private HttpServletRequest request;

    private User user1 = new User();

    private User user2;

    private String sex;

    public User getUser2() {

        return user2;

    }

    public void setUser2(User user2) {

        this.user2 = user2;

    }

    public String getSex() {

        return sex;

    }

    public void setSex(String sex) {

        this.sex = sex;

    }

    public String add() {

        System.out.println("add方法");

        return "success";

    }

    public String edit() {

        System.out.println("edit方法");

        return "success";

    }

    public String del() {

        System.out.println("del方法");

        return "success";

    }

    public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        System.out.println("user2:"+user2);

        System.out.println("sex:"+sex);

        //非注入--耦合型

//        HttpServletRequest request = ServletActionContext.getRequest();

//        request.setAttribute("rs", user1);

        this.request.setAttribute("rs",user1);

        return "success";

    }

    @Override

    public User getModel() {

        // TODO Auto-generated method stub

        return user1;

    }

    @Override

    public void setServletRequest(HttpServletRequest request) {

        this.request=request;

    }

    @Override

    public void setServletResponse(HttpServletResponse response) {

        this.response=response;

    }

}

1.2导入的外部xml文件

1.2.1 pom.xml

在pom.xml中插入此段代码

<dependency>

            <groupId>org.apache.struts</groupId>

            <artifactId>struts2-core</artifactId>

            <version>2.5.13</version>

        </dependency>

1.2.2 struts-base.xml

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

<!DOCTYPE struts PUBLIC

    "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"

    "http://struts.apache.org/dtds/struts-2.5.dtd">

<struts>

    <constant name="struts.i18n.encoding" value="UTF-8" />

    <constant name="struts.devMode" value="true" />

    <constant name="struts.configuration.xml.reload" value="true" />

    <constant name="struts.i18n.reload" value="true" />

    <constant name="struts.enable.DynamicMethodInvocation" value="true" />

    <package name="base" extends="struts-default" abstract="true">

        <global-allowed-methods>regex:.*</global-allowed-methods>

    </package>

</struts>

1.2.3 struts-sy.xml

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

<!DOCTYPE struts PUBLIC

    "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"

    "http://struts.apache.org/dtds/struts-2.5.dtd">

<struts>

    <package name="sy" extends="base" namespace="/sy">

      <action name="/hello_*" class="com.yuan.web.HelloAction" method="{1}">

        <result name="success">/success.jsp</result>

      </action>

    </package>

</struts>

1.2.4 struts.xml

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

<!DOCTYPE struts PUBLIC

    "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"

    "http://struts.apache.org/dtds/struts-2.5.dtd">

<struts>

    <include file="struts-default.xml"></include>

    <include file="struts-base.xml"></include>

    <include file="struts-sy.xml"></include>

</struts>

1.2.5 web.xml

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"

         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"

         version="3.1">

  <display-name>Archetype Created Web Application</display-name>

  <filter>

    <filter-name>struts2</filter-name>
    //ctrl+shift+t 搜索StrutsPrepareAndExecuteFilter,点开第一个，右键拷出全路径名粘贴到此处

    <filter-class>org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>

  </filter>

  <filter-mapping>

    <filter-name>struts2</filter-name>

    <url-pattern>*.action</url-pattern>

  </filter-mapping>

</web-app>

1.3新建jsp

1.3.1 demo1.jsp 代码会有报错的假象，不用管

 <%@ page language="java" contentType="text/html; charset=UTF-8"

     pageEncoding="UTF-8"%>

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

 <html>

 <head>

 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

 <title>Insert title here</title>

 </head>

 <body>

 <h2>struts传参的三种方式</h2>

 <a href="${pageContext.request.contextPath }/sy/hello_list.action?uid=001&&uname=zs">测试modeldriven接口传参</a>&nbsp;&nbsp;

 <a href="${pageContext.request.contextPath }/sy/hello_list.action?sex=nv">测试set传参</a>&nbsp;&nbsp;

 <a href="${pageContext.request.contextPath }/sy/hello_list.action?user2.uid=002&&user2.uname=ls">测试参数名.属性名传参</a>

 <h2>与j2EE容器的交互</h2>

 </body>

 </html>

1.3.2 success.jsp

 <%@ page language="java" contentType="text/html; charset=UTF-8"

     pageEncoding="UTF-8"%>

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

 <html>

 <head>

 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

 <title>Insert title here</title>

 </head>

 <body>

 成功页面:${rs }

 </body>

 </html>

2、动态调用方法（mvc不具备的优势）

2.1 action代码

     public String add() {

         System.out.println("add方法");

         return "success";

     }

     public String edit() {

         System.out.println("edit方法");

         return "success";

     }

2.2 jsp代码

<h2>动态调用方法</h2>

<a href="${pageContext.request.contextPath }/sy/hello_add.action">add方法</a>

<a href="${pageContext.request.contextPath }/sy/hello_edit.action">edit方法</a>

后台输出调用的相对应的方法

3、struts中的传参

3.1、实现 modelDrivern接口传参

3.1.1 action代码

public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        }

3.1.2 jsp代码

<a href="${pageContext.request.contextPath }/sy/hello_list.action?uid=001&&uname=zs">测试modeldriven接口传参</a>&nbsp;&nbsp;

后台输出显示：user1:User [uid=001, uname=zs]

3.2 set传参

3.2.1 action代码

 public String list() {

         System.out.println("list方法");

         System.out.println("sex:"+sex);         }

3.2.2 jsp代码

<a href="${pageContext.request.contextPath }/sy/hello_list.action?sex=nv">测试set传参</a>&nbsp;&nbsp;

后台输出显示：sex:nv

3.3类实例.属性名

3.3.1 action代码

 public String list() {

          System.out.println("list方法");

          System.out.println("user2:"+user2);

          }

3.3.2 jsp代码

<a href="${pageContext.request.contextPath }/sy/hello_list.action?user2.uid=002&&user2.uname=ls">测试参数名.属性名传参</a>

后台输出显示：user2:User [uid=002, uname=ls]

4、struts与tomcat的交互

4.1 request传值，需要实现ModelDriven接口，调用ServletActionContext.getRequest()方法。

如：

public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        System.out.println("user2:"+user2);

        System.out.println("sex:"+sex);

        HttpServletRequest request = ServletActionContext.getRequest();

        request.setAttribute("rs", user1);

        return "success";

    }

前台页面显示：成功页面:User [uid=001, uname=zs]

4.2 值栈传值（get方法传值），不需要操作，因为值栈传值会将传过来的值自动赋值

public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        System.out.println("user2:"+user2);

        System.out.println("sex:"+sex);

        return "success";

    }

前台页面显示：成功页面:User [uid=002, uname=ls]

5、注入与非注入

5.1 注入，注入需要实现ServletRequestAware接口，重写需要实现的方法setServletRequest；

将setServletRequest方法的参数私有化作为属性

private HttpServletRequest request;

setServletRequest方法

@Override

    public void setServletRequest(HttpServletRequest request) {

        this.request=request;

    }

属性调用

public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        System.out.println("user2:"+user2);

        System.out.println("sex:"+sex);

        this.request.setAttribute("rs",user1);

        return "success";

    }

5.2 非注入

request传值就是属于非注入

public String list() {

        System.out.println("list方法");

        System.out.println("user1:"+user1);

        System.out.println("user2:"+user2);

        System.out.println("sex:"+sex);

        HttpServletRequest request = ServletActionContext.getRequest();

        request.setAttribute("rs", user1);

        return "success";

    }

谢谢观看^-^ ！！！

巴特西

struts2--入