private static ObjectNode putNullableAttribute(ObjectNode node, String name, String value) {
        if (value != null) {
            node.put(name, value);
        }
        return node;
    }
User: michaels@netflix.com
Date: 9/2/14
Time: 2:52 PM
zuul-core/src/main/java/com/netflix/zuul/niws/RequestAttempt.java