XML中的列表标记。 我不明白它的作用

Question

This is a question related to Spring MVC. I have entries in an XML file like this.

<bean class="org.springframework.web...DefaultAnotationHandlerMapping">
    <property name="interceptors">
        <list>
          <bean class="rewardsonline.AuditInterceptor"/>
          <bean class="rewardsonline.PerformanceInterceptor"/>
        </list>
    </property>
</bean>

Now, I understand that the property called interceptors is an instance variable of the class DefaultAnnotationHandlerMapping. But, I cannot make sense of the list tag. What does that indicate?

Answer 1

The AbstractHandlerMapping class has a property called interceptors which is a List. The List element in the XML lists the interceptors which should be added to the interceptor list on AbstractHandlerMapping when it's initialized.

Answer 2

4.4.2.4 Collections

In the <list/> , <set/> , <map/> , and <props/> elements, you set the properties and arguments of the Java Collection types List , Set , Map , and Properties , respectively.

Your XML fragment is constructing a java.util.List and injecting it ino the interceptors property of the DefaultAnotationHandlerMapping object.