documentclass[border=5pt]{standalone}
usepackage{tikz}
usetikzlibrary{positioning,calc}
usepackage{tikz-uml}

begin{document}
tinybegin{tikzpicture}[show background grid]
    defdx{0.5cm}
    defdy{1.5cm}
    umlclass{AAAAAA}{}{};
     umlclass[left=dx of AAAAAA]{BBBBBBBBB}{}{};
     umlclass[right=dx of AAAAAA]{C}{}{};
    umlclass[below=dy of AAAAAA]{D}{}
    {+foo()\
    +bar()\
    +hello()};
    umlclass[below=dy of D]{E}{}{};

    node[circle,fill=black] (M) at ($(D)!0.5!(AAAAAA)$) {};
     umlinherit[geometry=-|]{D}{AAAAAA};
     umlinherit[geometry=-|]{M}{BBBBBBBBB};
     umlinherit[geometry=-|]{M}{C};
end{tikzpicture}
end{document}