anchor.diff:      ;
   
   classDeclaration
  -    :   normalClassDeclaration
  -    |   enumDeclaration
  -    ;
  -    
  -normalClassDeclaration
       :   'class' Identifier typeParameters?
           ('extends' type)?
           ('implements' typeList)?
  
positive.code:     
  blockStatement
      :   localVariableDeclarationStatement
      |   classOrInterfaceDeclaration
      |   statement
      ;
      
  localVariableDeclarationStatement
  
negative.code:     
  annotationTypeElementRest
      :   type annotationMethodOrConstantRest ';'
      |   classDeclaration ';'?
      |   interfaceDeclaration ';'?
      |   enumDeclaration ';'?
      |   annotationTypeDeclaration ';'?
      ;
  