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Classes and class members should be given minimum possible access so that malicious code has the least opportunity to compromise security. As far as possible, classes should avoid exposing methods that contain (or invoke) [sensitive code|BB. Definitions#sensitive code] through interfaces; interfaces allow only publicly accessible methods, and such methods are part of the public Application Programming Interface (API) of the class. (Note that this is the opposite of Bloch's recommendation to prefer interfaces for APIs \[[Bloch 2008|AA. Bibliography#Bloch 08], Item 16\].) One exception to this is implementing an _unmodifiable_ interface that exposes a public immutable view of a mutable object. (See rule [void SEC14OBJ08-J. Provide sensitive mutable classes with unmodifiable wrappers copy functionality to allow passing instances to untrusted code safely].) Additionally, note that even if a non-final class's visibility is default, it can be susceptible to misuse if it contains public methods. Methods that perform all necessary security checks, as well as sanitizing all inputs, can also be exposed through interfaces.