Mutable ``static`` members which are accessed directly, rather than through getters and setters, should be protected to the degree possible. That can be done by reducing visibility or making the field ``final`` if appropriate. Note that making a mutable field, such as an array, ``final`` will keep the variable from being reassigned, but doing so has no effect on the mutability of the internal state of the array (i.e. it doesn't accomplish the goal).