How to call a method after bean initialization is complete?

user_133830 0
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I have a use case where I need to call a (non-static) method in the bean only-once at the ApplicationContext load up. Is it ok, if I use MethodInvokingFactoryBean for this? Or we have a some better solution?

As a side note, I use ConfigContextLoaderListener to load the Application Context in web application. And want, that if bean 'A' is instantiated just call methodA() once.

How can this be done nicely?

applicationcontext startup initialization spring
6 Answers

You can use something like:

<beans>
    <bean id="myBean" class="..." init-method="init"/>
</beans>

This will call the "init" method when the bean is instantiated.

user_1308320

There are three different approaches to consider, as described in the reference

Use init-method attribute

Pros:

  • Does not require bean to implement an interface.

Cons:

  • No immediate indication in source code that this method is required after construction to ensure the bean is correctly configured.

Implement InitializingBean

Pros:

  • No need to specify init-method, or turn on component scanning / annotation processing.
  • Appropriate for beans supplied with a library, where we don't want the application using this library to concern itself with bean lifecycle.

Cons:

  • More invasive than the init-method approach.

Use JSR-250 @PostConstruct lifecyle annotation

Pros:

  • Useful when using component scanning to autodetect beans.
  • Makes it clearer that a specific method is to be used for initialisation. Intent is closer to the code.

Cons:

  • Initialisation no longer centrally specified in configuration.
  • You must remember to turn on annotation processing (which can sometimes be forgotten)
toolkit_32950

Have you tried implementing InitializingBean? It sounds like exactly what you're after.

The downside is that your bean becomes Spring-aware, but in most applications that's not so bad.

user_226560

You could deploy a custom BeanPostProcessor in your application context to do it. Or if you don't mind implementing a Spring interface in your bean, you could use the InitializingBean interface or the "init-method" directive (same link).

user_956990
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