Re: newInstance, generics, and "unchecked or unsafe operations"
Fri, 15 Aug 2008 00:08:17 -0700, /Eric I./:
I'm trying to create a method in a class that takes some type of
genericized collection and creates a new, empty instance of it by
calling the newInstance method. I can get the code to work, but I do
get compiler warnings of "unchecked or unsafe operations".
public Collection<T> duplicateEmptyVersionOf(Collection<T>
throws InstantiationException, IllegalAccessException
// COMPILER WARNING on next line; BUT I KNOW T at compile-
Collection<T> emptyVersionOf =
Recently one has mentioned the Class.asSubclass  method but I
can't figure out which is the correct syntax, or if it is possible
Class<? extends Collection<T>> c;
// Syntax error in the |Collection<T>.class| part.
c = original.getClass().asSubclass(Collection<T>.class);
Collection<T> emptyVersionOf = c.newInstance();
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