if (document == null) {
document = new FIXSessionBrowserDocumentComponent(messageCache, key1);
documents.put(key1, document);
documents.put(key2, document);
addTaskListener(document) ;
document.addDocumentComponentListener(new DocumentComponetListenerSupport(){
@Override
public void documentComponentClosed(DocumentComponentEvent arg0) {
stop() ;
}
}) ;