/** * Adds a won:hasTextMessage triple to one of the unsigned content graphs in this builder. Creates a new * unsigned content graph if none is found. * @param textMessage may be null in which case the builder is not modified * @return */ public WonMessageBuilder setTextMessage(String textMessage){ if (textMessage != null) { WonRdfUtils.MessageUtils.addMessage(getUnsignedContentGraph(), textMessage); } return this; }