String (List<ResolvedClassType> objects) { String fieldName = null; for (ResolvedClassType type : objects) { JsonNode properties = type.node.get("properties"); if (properties == null || !properties.isObject()) return null; for (Iterator<Map.Entry<String, JsonNode>> it = properties.fields(); it.hasNext(); ) { Map.Entry<String, JsonNode> property = it.next(); if (getConstString(property.getValue()) != null) { if (fieldName == null) { fieldName = property.getKey(); } else if (!property.getKey().equals(fieldName)) { return null; } } } } return fieldName; }