The Java® Language Specification, Java SE 7 Edition, Fourth Edition

8.1. Class Declarations

A class declaration specifies a new named reference type.

There are two kinds of class declarations: normal class declarations and enum declarations.

ClassDeclaration:    NormalClassDeclaration    EnumDeclarationNormalClassDeclaration:    ClassModifiers_opt class Identifier TypeParameters_opt                                            Super_opt Interfaces_opt ClassBody

The rules in this section apply to all class declarations unless this specification explicitly states otherwise. In many cases, special restrictions apply to enum declarations (§8.9).

The Identifier in a class declaration specifies the name of the class.

It is a compile-time error if a class has the same simple name as any of its enclosing classes or interfaces. ...