@Override
    public DocumentId readDocumentId() {
        Utf8String uri = new Utf8String(parseNullTerminatedString(getBuf().getByteBuffer()));
        return DocumentId.createFromSerialized(uri.toString());
    }
Class used for de-serializing documents on the Vespa 6.x document format.

@author baldersheim
document/src/main/java/com/yahoo/document/serialization/VespaDocumentDeserializer6.java