@implSpec
This implementation iterates over <tt>entrySet()</tt> searching
for an entry with the specified key. If such an entry is found,
the entry's value is returned. If the iteration terminates without
finding such an entry, <tt>null</tt> is returned. Note that this
implementation requires linear time in the size of the map; many
implementations will override this method.
{@inheritDoc}
@implSpec This implementation iterates over <tt>entrySet()</tt> searching for an entry with the specified key. If such an entry is found, the entry's value is returned. If the iteration terminates without finding such an entry, <tt>null</tt> is returned. Note that this implementation requires linear time in the size of the map; many implementations will override this method.
@throws ClassCastException {@inheritDoc} @throws NullPointerException {@inheritDoc}