private StructureEditor textStructureEditor(SourceTarget st) {
TextDocumentId id = (st == SourceTarget.Source) ? transformation.getSourceTextDocumentId()
: transformation.getTargetTextDocumentId();
IntegrationProject project = ProjectUtils.getProject(transformation);
TextDocument doc = project.getItemLookup().getEntity(id, TextDocument.class);
return new TextStructureEditor(doc, st, explorerSupport);
}