Java/TypeChecking
From charlesreid1
This gets complicated fast when you're using generic types.
Neal Grafter's blog has a page talking about reified generics. This has to do with casting objects to generic types, and casting to objects that utilize the diamond notation, like Collections objects.
This stack overflow question addresses some similar issues.
The approach that introduces the least amount of conflict is to use (Object o) as a parameter type, then cast to whatever type you need. If you must cast to a type that takes generic parameter types, like a Map or a Set, you can explicitly tell the complier not to complain by adding the decorator @SuppressWarnings("unchecked"). See this stack overflow question for some additional information.