Graphviz

digraph {
    graph [pad="0.5", nodesep="0.5", ranksep="2"];
    node [shape=plain]
    rankdir=LR;
	NormalUser [label=<
	<table border="0" cellborder="1" cellspacing="0">
	  <tr><td><i>NormalUser</i></td></tr>
	  <tr><td port="1">facebookId</td></tr>
	  <tr><td port="2">topic</td></tr>	  
	</table>>];


	StaffUser [label=<
	<table border="0" cellborder="1" cellspacing="0">
	  <tr><td><i>StaffUser</i></td></tr>
	  <tr><td port="2">managerId</td></tr>
	  <tr><td port="3">permissions</td></tr>	  
	</table>>];


	AbstractUser [label=<
	<table border="0" cellborder="1" cellspacing="0">
	  <tr><td><i>AbstractUser</i></td></tr>
	  <tr><td port="a">firstName</td></tr>
	  <tr><td port="b">lastName</td></tr>
	  <tr><td port="c">birthdate</td></tr>
	  <tr><td port="d">email</td></tr>
	  <tr><td port="e">password</td></tr>	  
	</table>>];

	NormalUser:1 -> AbstractUser:a;
	StaffUser:2 -> AbstractUser:a;
}