code: public <T> T isInstanceOf(final Class<?> type, final T obj) {
          if (!type.isInstance(obj)) {
              fail(String.format(DEFAULT_IS_INSTANCE_OF_EX_MESSAGE, type.getName(), obj == null ? "null" : obj.getClass().getName()));
          }
          return obj;
      }
docs: Validates that the argument is an instance of the specified class, if not throws an exception. <p>This method is useful when validating according to an arbitrary class</p>
  <pre>Validate.isInstanceOf(OkClass.class, object);</pre>
  <p>The message of the exception is &quot;Expected type: {type}, actual: {obj_type}&quot;</p>
  
  @param <T>
  the type of the object
  @param type
  the class the object must be validated against, not null
  @param obj
  the object to check, null throws an exception
  
  @return the object
  
  @throws IllegalArgumentValidationException
  if argument is not of specified class
  @see #isInstanceOf(Class, Object, String, Object...)