Abstract classes with Grails?

[filot]

Hello,

Is it possible to work with abstract classes in Grails, like in Java!? It seems to me that it's possible with Groovy, but with Grails I have a compilation problem when I declare a class as "abstract"...


I am using the STS IDE for the development, when I save a class as "abstract", I have this message, before the server shuts down:

2011-02-06 18:24:48,793 [main] ERROR context.GrailsContextLoader  - Error executing bootstraps: Error creating bean with name 'messageSource': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is java.lang.NullPointerException
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageSource': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is java.lang.NullPointerException
	at org.grails.tomcat.TomcatServer.start(TomcatServer.groovy:212)

I understand that we cannot generate a view for an abstract class... but then how to deal with abstract classes in Grails?

I have a class A, and I want to say that it has as attributes a set of objects belonging to the abstract class B:

abstract class B {

    static constraints = {
    }	
}

class A {

    static constraints = {
    }	
	static hasMany = [b:B]	
}

Is it possible with Grails!? I guess the answer is yes... well I hope... but how!?

Thanks a lot.

[Andy Clement]

Hi,

Looks like you are hitting a variant of these issues which discuss the use of abstract classes:
http://jira.codehaus.org/browse/GRAILS-5356
http://jira.codehaus.org/browse/GRAILS-2583
http://jira.codehaus.org/browse/GRAILS-6780

there are probably others. Looks like grails 1.4 is intended to fix issues related to abstract classes. If you want more background, I recommend contacting the grails guys on their user list or in the grails forum: http://forum.springsource.org/forumdisplay.php?f=76

cheers
Andy
---
Andy Clement
SpringSource Tool Suite Team

[filot]

Hello, ans thank you for your answer.

didn't know there is a GRAILS forum, I asked the question there.