org.springframework.context.ApplicationContextAware

Spring中提供一些Aware相关接口，像是BeanFactoryAware、 ApplicationContextAware、ResourceLoaderAware、ServletContextAware等等，实现这些 Aware接口的Bean在被初始之后，可以取得一些相对应的资源。例如实作ApplicationContextAware的Bean，在Bean被初始后，将会被注入 ApplicationContext的实例等等。　Bean取得BeanFactory、ApplicationContextAware的实例目的是什么，一般的目的就是要取得一些档案资源的存取、相 关讯息资源或是那些被注入的实例所提供的机制

import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationContext;
import org.springframework.beans.BeansException;
public class GlobalParamUtils implements ApplicationContextAware {
     private static ApplicationContext ac;

      public void setApplicationContext(ApplicationContext arg0) throws BeansException {
this.ac = arg0;
      }
 public static String generateCodeByType(String type) {
    String result = "";
    if (ac.containsBean("swmsBussinessCodeManager")) {
    BussinessCodeManager codeManager = (BussinessCodeManager) ac.getBean("swmsBussinessCodeManager");
    try {
        Method method = codeManager.getClass().getMethod(type, new Class[0]);
result = (String) method.invoke(codeManager, new Object[0]);
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (SecurityException e) {
e.printStackTrace();
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
    }
    return result;
    }
}

 

//swmsBussinessCodeManager在bean中的配置

<bean class="com.vtradex.swms.server.service.GlobalParamUtils"/>
        <bean id="swmsBussinessCodeManager" parent="abstractTransactionProxy">
           <property name="target">
                    <bean class="com.vtradex.swms.server.service.sequence.pojo.DefaultBussinessCodeManager" parent="baseManager">
 <constructor-arg index="0">
<ref bean="sequenceGenerater"/>
</constructor-arg>
<constructor-arg index="1">
<ref bean="swmsSequenceDao"/>
</constructor-arg>
     </bean>
           </property>
</bean>

 

基本上，Spring虽然提供了这些Aware相关接口，然而Bean上若实现了这些界面，就算是与Spring发生了依赖，从另一个角度来看，虽然您可以直接在Bean上实现这些接口，但您也可以透过setter来完成依赖注入，例如：

 

public class GlobalParamUtils {
     private static ApplicationContext ac;

      public void setApplicationContext(ApplicationContext arg0) throws BeansException {
this.ac = arg0;
      }
 public static String generateCodeByType(String type) {
    String result = "";
    if (ac.containsBean("swmsBussinessCodeManager")) {  
    BussinessCodeManager codeManager =                          (BussinessCodeManager)ac.getBean("swmsBussinessCodeManager");
    try {
        Method method = codeManager.getClass().getMethod(type, new Class[0]);
result = (String) method.invoke(codeManager, new Object[0]);
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (SecurityException e) {
e.printStackTrace();
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
    }
    return result;
    }
}

 

注意这次我们并没有实作ApplicationContextAware，我们在程序中可以自行注入ApplicationContext实例：

ApplicationContext context = new ClassPathXmlApplicationContext("service.xml");

 

就Bean而言，降低了对Spring的依赖，可以比较容易从现有的框架中脱离