Struts2的Action访问Spring的业务逻辑组件的两种策略

1、让spring管理控制器Action,并利用依赖注入为控制器注入业务逻辑组件

业务逻辑代码

package service;public class MyService {    public boolean validLogin(String username,String password){        //简单的验证逻辑：用户名为张三且密码为123456则登录成功        if("张三".equals(username)&&"123456".equals(password)){            return true;        }        return false;    }}

控制器Action代码

package controller;import com.opensymphony.xwork2.ActionSupport;import service.MyService;public class LoginAction extends ActionSupport{    private String username;    private String password;    private MyService myService;    //用于spring依赖注入    public void setMyService(MyService myService) {        this.myService = myService;    }    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 execute(){        if(myService.validLogin(getUsername(), getPassword())){            return SUCCESS;        }        return ERROR;    }}

applicationContext.xml配置

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xmlns:context="http://www.springframework.org/schema/context"    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">    <bean id="myService" class="service.MyService"></bean>    <!-- 注意：控制器Action的scope要设置为prototype -->    <bean id="loginAction" class="controller.LoginAction" scope="prototype">        <property name="myService" ref="myService"></property>    </bean></beans>

struts.xml配置

<?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>    <constant name="struts.i18n.encoding" value="UTF-8"></constant>    <constant name="struts.devMode" value="true"></constant>    <package name="default" extends="struts-default">        <!-- 使用spring容器管理的Action控制器：此处class为spring容器中bean的id -->        <action name="login" class="loginAction">            <result name="error">/error.jsp</result>            <result>/welcome.jsp</result>        </action>    </package></struts>

2、利用spring的自动装配方式，Action会自动重spring容器中获取所需的逻辑组件

业务逻辑和控制器Action代码一样，applicationContext.xml代码如下

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xmlns:context="http://www.springframework.org/schema/context"    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">    <!--这里只需要配置业务逻辑的bean-->    <bean id="myService" class="service.MyService"></bean></beans>

struts.xml

<?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>    <constant name="struts.i18n.encoding" value="UTF-8"></constant>    <constant name="struts.devMode" value="true"></constant>    <package name="default" extends="struts-default">        <!-- 这里class属性不再是spring中bean的id,而是控制器的全类名-->        <action name="login" class="controller.LoginAction">            <result name="error">/error.jsp</result>            <result>/welcome.jsp</result>        </action>    </package></struts>

从控制台中可以看出struts2-spring-plugin-2.3.24.1.jar使用自动装配的方式是通过名字来自动装配的
通过设置struts.objectFactory.spring.autoWire常量改变spring插件的自动装配方式，该常量接受如下几个值：

• name:使用byName自动装配
• type:使用byType自动装配
• auto:spring插件自动检测需要哪种装配方式
• constructor:与type类似，区别是使用构造器来构造注入所需的参数，而不是使用setter方式注入

详细请参看《轻量级java ee 企业应用实战》李刚