Programmer's Guide to Java™ Certification, A: A Comprehensive Primer, Second Edition

7.3. Non-static Member Classes

Non-static member classes are inner classes that are defined without the keyword static, as members of an enclosing class or interface. Non-static member classes are on par with other non-static members defined in a class. The following aspects about non-static member classes should be noted:

• An instance of a non-static member class can only exist with an instance of its enclosing class. This means that an instance of a non-static member class must be created in the context of an instance of the enclosing class. This also means that a non-static member class cannot have static members. In other words, the non-static member class does not provide any services, only instances of the class do. However, final static ...