Can spring change class dynamatically?

[Kurt Xu]

Such as add a method , a field at runtime stage on a web application.

[Nathan Pruett]

No, Java doesn't let you do this, so Spring won't either.

[Mark Spritzler]

Actually, you can with Spring AOP.

It is called Introductions, and here is a link to the docs that shows how to do this

http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/aop.html#aop-introductions

Mark

[Kurt Xu]

Mark Spritzler wrote:Actually, you can with Spring AOP.

It is called Introductions, and here is a link to the docs that shows how to do this

http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/aop.html#aop-introductions

Mark

To be exact, introduction need to be done at compilation time ,not runtime, cause at that moment ,bean has been created.

thanks.

[Shashank Ag]

Well some byte code manuplation apis are availble like Javassist.
But, I am still interested why AOP will not work in your case.
Have you really read the concept? Don't mind its just I am big fan of spring AOP.

[Bang Nguyen]

Mark Spritzler wrote:Actually, you can with Spring AOP.

It is called Introductions, and here is a link to the docs that shows how to do this

http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/aop.html#aop-introductions

Mark

Hi, actually I don't believe IntroductionInterceptor can change class dynamically. I think it can intercept and add additional features that the original Java class doesn't have. I posted a question regarding this. Check it out and see if it's your case or not:

How to use IntroductionInterceptor...

[Kurt Xu]

Shashank Ag wrote:Well some byte code manuplation apis are availble like Javassist.
But, I am still interested why AOP will not work in your case.
Have you really read the concept? Don't mind its just I am big fan of spring AOP.

well, javassist can't change class behavior after they are created, but that's exactly what I need.

[Mark Spritzler]

These introduction methods are added to the code via AOP/Proxies and are created at runtime, not a special compile time thing to do. Spring AOP creates DynamicProxies at runtime.

Mark