public AceSelection getSelection() {
        if (selection == null) {
            selection = new AceSelection(getSelectionJS());
        }
        return selection;
    }
Prepare a wrapper around Ace Selection object.

@return a wrapper around Ace Selection object
stroom-core-client-widget/src/main/java/edu/ycp/cs/dh/acegwt/client/ace/AceEditor.java