@Test
    public void testFallback_fallbackSet() {
        ConfigurationManager.getConfigInstance().setProperty(DEFAULT_INTEGER_PROPERTY.key(), "100");
        DefaultClientConfigImpl clientConfig = new DefaultClientConfigImpl();
        Property<Integer> prop = clientConfig.getGlobalProperty(INTEGER_PROPERTY.format(testName.getMethodName()))
                .fallbackWith(clientConfig.getGlobalProperty(DEFAULT_INTEGER_PROPERTY));

        Assert.assertEquals(100, prop.getOrDefault().intValue());
    }
Test cases to verify the correctness of the Client Configuration settings

@author stonse
ribbon-core/src/test/java/com/netflix/client/config/ClientConfigTest.java