InjectionMetadata and LifecycleMetadata can end up having mostly empty
instance variables. In such cases memory usage can be improved a little
bit.
This patch addresses this in two ways:
- Creating a LinkedHashSet of the "right" size, the default capacity
is 16 but the exact capacity needed is known in advance.
- If the argument is empty then use Collections#emptySet which is a
constant so no additional memory is used. Since it's immutable there
is no need for the Collections#synchronizedSet wrapper.
Issue: SPR-9264
cdb6d7447e