public static TypeParameter superOf(String fullyQualifiedClassName) {
   TypeParameter p = new TypeParameter(fullyQualifiedClassName);
   p.wildcardExpression = "? super ";
   return p;
 }
 public static TypeParameter wildcard() {
   TypeParameter p = new TypeParameter("");
   p.wildcardExpression = "?";
   return p;
 }
 public static TypeParameter extending(String fullyQualifiedClassName) {
   TypeParameter p = new TypeParameter(fullyQualifiedClassName);
   p.wildcardExpression = "? extends ";
   return p;
 }