Struts2 （一）入门

使用Struts 2 开发程序的基本步骤

1、加载Struts2 类库

　　需要的maven节点：

<dependency>
    <groupId>javaee</groupId>
    <artifactId>javaee-api</artifactId>
    <version>5</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.apache.struts/struts2-core -->
<dependency>
    <groupId>org.apache.struts</groupId>
    <artifactId>struts2-core</artifactId>
    <version>2.3.16.3</version>
</dependency>


<!-- https://mvnrepository.com/artifact/org.apache.struts.xwork/xwork-core -->
<dependency>
    <groupId>org.apache.struts.xwork</groupId>
    <artifactId>xwork-core</artifactId>
    <version>2.3.16.3</version>
</dependency>

2、配置web.xml文件

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>
  <!--过滤器-->
  <filter>
    <filter-name>struts2</filter-name>
    <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>

  <filter-mapping>
    <filter-name>struts2</filter-name>
    <!--拦截所有方法-->
    <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

3、开发视图层页面

4、开发控制层Action

public class LoginAction implements Action {
    private String username;
    private String password;
    public String execute() throws Exception {
        if (username.equals("admin")&&password.equals("admin")){
            return SUCCESS;
        }else {
            return LOGIN;
        }

    }

5、配置struts.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
        "http://struts.apache.org/dtds/struts-2.3.dtd ">
<struts>
    <!-- 配置文件中只要添加以下配置，那么以后修改配置文件不用重启tomcat -->
    <constant name="struts.devMode" value="true" />
<package name="default" namespace="/" extends="struts-default">
<!--零散属性装配-->
    <action name="islogin" class="cn.happy.day01.LoginAction">
        <result name="success">day01/index.jsp</result>
        <result name="login">day01/login.jsp</result>
    </action>
</package>

</struts>

web.xml

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>
  <filter>
    <filter-name>struts</filter-name>
    <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>struts</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>