while using Spring ApplicationContext as in the example below, are annotations taken care of

Question

public class SomeClass {
    @Autowired
    public WaterContainer wc;

    private static int count = 0;

    SomeClass(){ ++count;}

    public static int testmethod() {
        return count;
    }

    public static void main(String[] args) {
        ApplicationContext context = new FileSystemXmlApplicationContext("spring-configuration\\beans.xml");

        SomeClass obj = context.getBean(SomeClass.class);
        //SomeClass obj2 = new SomeClass();
        System.out.println("value of count "+SomeClass.testmethod());
        if(obj.wc != null)
            System.out.println("wc volume "+obj.wc.getCurrentVolume());
        else
            System.out.println("wc bean "+context.getBean(WaterContainer.class).getCurrentVolume()); //+(obj.wc==null)
    }
}

The beans.xml file contains this :

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

    <bean class="com.app.data.SomeClass"/>
    <bean class="com.app.mechanism.WaterContainer">
        <constructor-arg value="30"/>
    </bean>

</beans>

the output that I got was as below but I expected the field wc in the SomeClass object to not be null, does that mean autowired annotations are not taken care of? or have I gone wrong somewhere?
value of count 1
wc bean 30

If so then how does
@RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations = {"file:spring-configuration\\beans.xml"})
work for unit testing? how is the autowiring taken care of here

If annotations are processed automatically depends on the type of `ApplicationContext` used. The one you use doesn't proces annotations, as you already noticed. To enable the annotation processing ass ``. Or use an `AnnotationConfigApplicationContext` and feed it the xml file. — M. Deinum, Sep 03 '14 at 14:24

score 1 · Answer 1 · edited May 23 '17 at 11:57

1

As M. Deinum stated, annotation configuration is built into some ApplicationContext implementations and not in others.

FileSystemXmlConfiguration is an implementation that does not have annotation configuration built into it. You can enable that annotation configuration with

<context:annotation-config />

(and the relevant namespace declarations).

Since that configuration was not enabled, @Autowired fields were not processed, and your SomeClass#wc field was left null.

The test configuration you've shown internally uses an AnnotationConfigApplicationContext where annotation configuration is built in.

edited May 23 '17 at 11:57

Community

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answered Sep 03 '14 at 14:49

Sotirios Delimanolis

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when I use the tags in xml, `wc` is not null for `obj` but when I use `obj2` `wc` is still null – shrewquest Sep 04 '14 at 05:20
@shrewquest I'm assuming you mean `//SomeClass obj2 = new SomeClass();`. Notice how you are creating the object yourself. Spring is not involved in the least. – Sotirios Delimanolis Sep 04 '14 at 05:22

while using Spring ApplicationContext as in the example below, are annotations taken care of

1 Answers1