code: @GwtIncompatible("incompatible method")
      public static void isInstanceOf(final Class<?> type, final Object obj) {
          // TODO when breaking BC, consider returning obj
          if (!type.isInstance(obj)) {
              throw new IllegalArgumentException(StringUtils.simpleFormat(DEFAULT_IS_INSTANCE_OF_EX_MESSAGE, type.getName(),
                      obj == null ? "null" : obj.getClass().getName()));
          }
      }
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 type  the class the object must be validated against, not null
  @param obj  the object to check, null throws an exception
  @throws IllegalArgumentException if argument is not of specified class
  @see #isInstanceOf(Class, Object, String, Object...)
  
  @since 3.0