Can I use @PostConstruct on an interface method?

Question

I have a number of beans implementing an interface and I'd like them all to have the same @PostConstruct. I've added the @PostConstruct annotation to my interface method, then added to my bean definitions:

<bean class="com.MyInterface" abstract="true" />

But this doesn't seem to be working. Where am I going wrong if this is even possible?

edit: I've added the annotation to the interface like this:

package com;
import javax.annotation.PostConstruct;
public interface MyInterface {
    @PostConstruct
    void initSettings();
}

Show us more, please. What do you mean "added the annotation"? — Lee Meador, May 16 '13 at 14:04
I've added a little more of a code snippet. Does that help? Thank you — Abby, May 16 '13 at 14:06

score 15 · Accepted Answer · answered May 16 '13 at 14:20

The @PostConstruct has to be on the actual bean itself, not the Interface class. If you want to enforce that all classes implement the @PostConstruct method, create an abstract class and make the @PostConstruct method abstract as well.

public abstract class AbstractImplementation {

    @PostConstruct
    public abstract init(..);
}

public class ImplementingBean extends AbstractImplementation {
    public init(..) {
        ....
    }
}

score 1 · Answer 2 · answered May 16 '13 at 14:09

1

@PostConstruct has to go on the bean java class itself. I don't know what it will do on an interface.

Do you have this in your XML?

<context:annotation-config />

Here is some example code: @PostConstruct example

answered May 16 '13 at 14:09

Lee Meador

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Yes I have annotation-config in xml. Would I be able to use the interface as a parent defining an init-method? – Abby May 16 '13 at 14:12
No. The annotation has to go on the bean itself. – Lee Meador May 16 '13 at 14:12
I think it would be? e.g . I'll have a go with this and see what happens – Abby May 16 '13 at 14:14
Yes, seems to work. I think I will opt for using the abstract class on this occassion though as there are many beans which would need setting to have the parent. – Abby May 16 '13 at 14:36
It might be more descriptive to say you are using an abstract Spring bean since "class" could be taken to refer to the Java class which could be abstract as well. – Lee Meador May 16 '13 at 18:10
Yes - I mean abstract java class, not bean - as described in the other answer :) – Abby May 17 '13 at 07:49

Can I use @PostConstruct on an interface method?

2 Answers2