code: private static Class<?> extractClass(Class<?> ownerClass, Type arg) {
  		if (arg instanceof ParameterizedType) {
  			return extractClass(ownerClass, ((ParameterizedType) arg).getRawType());
  		}
  		else if (arg instanceof GenericArrayType) {
  			GenericArrayType gat = (GenericArrayType) arg;
  			Type gt = gat.getGenericComponentType();
  			Class<?> componentClass = extractClass(ownerClass, gt);
  			return Array.newInstance(componentClass, 0).getClass();
  		}
  		else if (arg instanceof TypeVariable) {
  			TypeVariable tv = (TypeVariable) arg;
  			arg = getTypeVariableMap(ownerClass).get(tv);
  			if (arg == null) {
  				arg = extractBoundForTypeVariable(tv);
  				if (arg instanceof ParameterizedType) {
  					return extractClass(ownerClass, ((ParameterizedType) arg).getRawType());
  				}
  			}
  			else {
  				return extractClass(ownerClass, arg);
  			}
  		}
  		return (arg instanceof Class ? (Class) arg : Object.class);
  	}
docs: Extract a Class from the given Type.