Friday Java Quiz: Generics
Today's quiz is inspired by the free Chapter of Joshua Bloch's Effective Java, 2nd Edition available from InfoQ.
There was a short time early last year when I used generics on the project, until I received the memo that said "We are using JDK 5 mainly for its runtime performance improvements. You can't actually use any of the JDK 5 language features." So my generics skills have rusted a little. The free chapter gave me a much needed refresher on generics.
Here's todays question:
Q: Will the following method compile?
public static <T extends Comparable<? super T>> T max(
List<? extends T> list) {
Iterator<T> i = list.iterator();
T result = i.next();
while (i.hasNext()) {
T t = i.next();
if (t.compareTo(result) > 0)
result = t;
}
return result;
}
The answer is in the sample chapter. Go read it.