Generics in static fields

Hi, I am trying to make a class which has some generic fields. I understand that it would not work just like that as the compiler has no way what the generic fields should actually be in a static context.
I want to use the generic class as an abstract class which would be extended, so that way the generics should be resolvable. Is there any way to make this work this way or should I not use generics and go type unsafe?
This is what I want to do in code:
abstract class ClassToBeExtended<A>
static A a;
class UsingTheOther extends ClassToBeExtended<String> {}

It is supposed to be a class that adds relations between other classes:
// Simplified
class RelationBetweenAandB extends TheClass<A, B> {}
class SomeOtherClass
void foo()
    A a = new A();
    B b1 = new B();
    B b2 = new B();
    RelationBetweenAandB.add(a, b1);
    RelationBetweenAandB.add(a, b2);
    new YetAnotherClass().listRelationsOf(a);
class YetAnotherClass
public void listRelationsOf(A a)
      for (B b : RelationBetweenAandB.allRhs(a))
      ; // Iterate through b1 and b2
}Having static fields will make the relation useful from anywhere in the application, if it is not static then all the objects that are going to be used in a relation have to instantiate the class which wlll probably introduce a lot of overhead.
abstract class SomeClass<A extends OtherClass>
static OtherClass a;
} Would require me to have Object in stead of OtherClass because I want all types of object to be in a relation, which is what I meant by going type unsafe :)
Message was edited by:
SavageNLD
Added some more reasoning about why I want static fields

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Juan Carlos

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Hi,
I've been googling for 2 days and it now seems I'm not understanding something because nobody seems to have my problem. Please, somebody tell me if I'm crazy.
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How can I share the static field between the 2 class loaders?
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zibilico wrote:
But maybe, if the web service stuff gets to complicated or it doesn't fulfill my needs, I'll set up a separate Spring context, that gets loaded everytime I run the "Java batch process". It'll have it's own Spring configuration files (these will be a fragment of the web app's config files), where I'll define only the beans I need to use, say the service and the 2 DAOs, and also the DB connection. Additionally, I'll set the classpath to use the beans classes of the web app. Thus, if the service and DAOs were modified in the app server, the process would load the modified classes in the following execution.You'll almost certainly have to do that even if you do use RMI, Web services etc. to connect.
What I suggest is that you split your web project into two source trees, the stuff that relates strictly to the web front end and the code which will be shared with the batch. The latter can then be treated as a library used by both the batch and web projects. That can include splitting Spring configuration files into common and specific, the common beans file can be retrieved from the classpath with an include. I regularly split web projects this way anyway, it helps impose decoupling between View/Controller and Model layers.
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excuse my wording. I have been using >= mostly, though
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TestLight.java:13: ')' expected
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Generics in static fields

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