One of the few times I've written a piece of functionality and actually found it later: the isInstance() method of the Class class. It's useful when you're dealing with generic classes and therefore cannot use instanceof:
void ensureAllHaveParent( Collection c, Class parentClass ) {
for ( Iterator it = c.iterator(); it.hasNext(); ) {
Object o = it.next();
if ( ! ( o instanceof parentClass ) ) ... // WRONG!
if ( ! parentClass.isInstance( o ) ) ... // RIGHT!
}
}
Posted from cwinters.com; read original