\begin{tikzpicture}%[scale=1,transform shape]

  \begin{class}{VirtualRoot}{-5,3}
  \end{class}
  
  \begin{class}{Classifier}{0,3}
    \attribute{name : String}
  \end{class}
 
  \begin{class}{DataType}{-5,0}
    \inherit{Classifier}
  \end{class}
  
  \begin{class}{Class}{0,0}
    \inherit{Classifier}
    \operation{isAbstract : boolean}
  \end{class}
  
  \begin{class}{Attribute}{5,0}
    \attribute{name : String}
  \end{class}


  \composition{VirtualRoot}{children}{0..*}{Classifier}
  \unidirectionalAssociation{Classifier}{root}{1}{VirtualRoot}
  
  \composition{Class}{attributes}{0..*}{Attribute}

  \unidirectionalAssociation{Attribute}{type}{1}{Classifier}

  %\myassociationtwo{Class}{subclass}{0..*}{Class}{0..*}{superclass}{-1,-3}{1,-3} %{210}
  \myassociationthree{Class}{subclass}{0..*}{Class}{0..*}{superclass}{-0.8,-2.5}{0.8,-2.5} %{210}
  %\association{Class}{subclass}{0..*}{Class}{superclass}{0..1} %{210}

\end{tikzpicture}