has a return type, a method parameter
 has a type, even the <code>extends</code> clause in a class declaration contains a type.
 Occurences of types may be annotated.
 <p>
 Types are:

 <ul>
 <li>the <a href="VoidType.html" title="interface in jakarta.enterprise.lang.model.types">void</a> pseudo-type</li>
 <li>a <a href="PrimitiveType.html" title="interface in jakarta.enterprise.lang.model.types">primitive</a> type, such as <code>int</code></li>
 <li>a <a href="ClassType.html" title="interface in jakarta.en