Spring method to destroy registry objects
I am currently converting spring config XML to Java annotations and I am facing a little annoying situation.
I need to create 3 beans that use the same class internally, but need to be separate instances. However, these internal beans need to register their shutdown method with Spring.
I can't think of how to do this without creating 9 beans in java (that's ok, but it seems a bit wrong to pollute the class like this)
In XML configuration, it looks like this:
<bean class="outer1">
<constructor-arg>
<bean class="middle">
<constructor-arg>
<bean class="inner" />
</constructor-arg>
</bean>
</constructor-arg>
</bean>
<bean class="outer2">
<constructor-arg>
<bean class="middle">
<constructor-arg>
<bean class="inner" />
</constructor-arg>
</bean>
</constructor-arg>
</bean>
<bean class="outer3">
<constructor-arg>
<bean class="middle">
<constructor-arg>
<bean class="inner" />
</constructor-arg>
</bean>
</constructor-arg>
</bean>
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One solution:
@Configuration
public class MyConfig{
@Bean(destroyMethod="cleanup")
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public Inner inner(){
return new Inner();
}
@Bean(destroyMethod="cleanup")
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public Middle middle(){
return new Middle(inner());
}
@Bean
public Outer outer1(){
return new Outer(middle());
}
@Bean
public Outer outer2(){
return new Outer(middle());
}
@Bean
public Outer outer3(){
return new Outer(middle());
}
}
From the reference documentation :
The non-elementary, prototypal bean deployment scope results in a new bean instance being created every time a request is made for that particular bean.
This means that every call to the middle () and inner () method creates a new instance of your bean.
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