code: public boolean isSubClassOf(TypeFinder typeFinder, String subClass, String superClass) throws JavaModelException {
  		final SuperTypeIterator typeIterator = new SuperTypeIterator(typeFinder, false, subClass);
  		while (typeIterator.hasNext()) {
  			final IType type = typeIterator.next();
  			if (Objects.equals(type.getFullyQualifiedName(), superClass)) {
  				return true;
  			}
  		}
  		return false;
  	}
docs: Replies if the given type is a subclass of the second type.
  
  <p>The type finder could be obtained with {@link #toTypeFinder(IJavaProject)}.
  
  @param typeFinder the type finder to be used for finding the type definitions.
  @param subClass the name of the sub class.
  @param superClass the name of the expected super class.
  @return <code>true</code> if it is a subclass.
  @throws JavaModelException if the Java model is invalid.
  @see #toTypeFinder(IJavaProject)