| Possible ClassModifiers are: |
| abstract -- Contains abstract methods without implementation -- typically such abstract classes have several subclasses that define implementation of methods |
| public -- May be used by code outside the class package and (unix) file must be called ClassName.java where ClassName is unique public class in file |
| private -- this class can only be used within current file -- i.e current class |
| friendly(i.e. empty ClassModifier) -- class can be used only within current package |
| protected -- Only accessible to subclasses |