private static String buildTypeName(StructuredDataType targetType) {
        return "Reference<" + targetType.getName() + ">";
    }
A <code>ReferenceDataType</code> specifies a particular concrete document type that a
{@link ReferenceFieldValue} instance binds to.

@author vekterli
document/src/main/java/com/yahoo/document/ReferenceDataType.java