CODEWITHSUNDEEP
javaclasscollections
aps
aps

Reputation: 2472

Collection of Classes

Is it possible to create a collection of different class types, so that an object can be later checked to see if it is an object of any of these classes in the collection? something like:

for(Class c: collectionOfClasses){
    if(o.getClass() == c){
        //do something
    }
}

Here, o is some object. I tried it out by using:

private LinkedList<Class> collectionOfClasses...

Eclipse gives a warning "Class is a raw type.References to generic type Class should be parameterized." Any safe way of doing what I want to do?

EDIT #1

Actually I have objects of different classes (which do not form a hierarchy), moving about. They all have a certain radius. A particular object can connect with other objects in its radius only if the other object falls into one of its known classes.could i make myself clear?

EDIT #2

A good example of what I want to do: Let's say I speak English and French. But I can identify different humans around me. Let's say I see 10 people near me. Then I will try to test if p1.getClass() is either English or French, p2.getClass() is either English or French. After all the humans around me are examined, I will talk to those who understand either English or French.

Upvotes: 5

Views: 9888

Answers (4)

phlogratos
phlogratos

Reputation: 13924

The for loop is not necessary. It's shorter just to write

if(collectionOfClasses.contains(o.getClass())) {
    //do something
}

Upvotes: 0

Lawrence McAlpin
Lawrence McAlpin

Reputation: 2785

Class is a generic type; to say you want 'any' kind of class, you would use the wildcard "?":

List<Class<?>> theList = ...

Upvotes: 1

RonK
RonK

Reputation: 9652

You can use:

private LinkedList<Class <?>> collectionOfClasses...

And if you have anything more specific, you can try:

private LinkedList<Class <? extends MyInterface>> collectionOfClasses...

Upvotes: 10

Marcelo
Marcelo

Reputation: 11308

You can use ArrayList<Class<?>>.

For example:

List<Class<?>> list = new ArrayList<Class<?>>();
list.add(String.class);
list.add(x.getClass());

Upvotes: 3

Related Questions