Android™ How to Program, Second Edition

F.13. Package Access

If no access modifier (public, protected or private) is specified for a method or variable when it’s declared in a class, the method or variable has package access. In a program that consists of one class declaration, this has no specific effect. However, if a program uses multiple classes from the same package (i.e., a group of related classes), these classes can access each other’s package-access members directly through references to objects of the appropriate classes, or in the case of static members through the class name. Package access is rarely used.