What does "Class

Question

I ran across this function definition :

public Collection<Class<? extends SomeClass>> someFunc();

What does the Class<? part mean? Coming from C++, it looks like templates, but I'm not quite sure if this is the case, since there are constructs in Java that look like C++, but aren't quite the same. In either case, I'd like to know what this means and how it's used.

I looked up what this meant, but I couldn't find anything relevant (perhaps there's a special name for this operator that I'm not aware of) - looking up "Class<? in Java" returned results similar to "what is a class in java". I'm fairly new to Java programming, so my apologies if this is something basic.

Thanks in advance.

https://www.google.com/?gws_rd=ssl#q=class+with+question+mark+java May the power of google be with you — austin wernli, Jun 24 '15 at 15:26
Also, why do you think it's `Class`? What about the `>` at the end? — Sotirios Delimanolis, Jun 24 '15 at 15:29

score 3 · Accepted Answer · answered Jun 24 '15 at 15:27

What you have come across is Java generics. Generics are Java's parallel to C++ templates. The question mark symbol ? stands for a wildcard.

To learn more, you can look for these terms or directly go to Oracle tutorial: https://docs.oracle.com/javase/tutorial/java/generics/

What does "Class

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