public void addText(String text) {
expression.add(new TextAdapter(text));
}
public void addStringref(IStringref istringref) {
Stringref stringref = (Stringref)istringref;
if (stringref.getDirectory() != null) {
expression.add(new TextAdapter(stringref.getDirectory()));
} else {
expression.add(stringref.getReference());
}
}