return defaultValue != null ? defaultValue.toString() : StringUtil.EMPTY;
        } catch (final Exception e) {
            return StringUtil.EMPTY;
        }
    }

    private String getDefaultMaxKey() {
        try {
            final Method method = CustomSize.class.getMethod("maxKey");
            final Object defaultValue = method.getDefaultValue();

            final Method method = UriType.class.getMethod("protocolType");
            assertNotNull("protocolType method should exist", method);
            assertNull("protocolType should not have default value", method.getDefaultValue());
        } catch (final NoSuchMethodException e) {
            fail("protocolType method should exist");
        }
    }

    // Test annotation hashCode and equals behavior