public void closeEmptySessions() { JInternalFrame[] frames = desktopPane.getAllFramesInLayer(0); for (JInternalFrame frame : frames) { Object o = frame.getContentPane().getComponents()[0]; if (o instanceof SessionEditor) { SessionEditor sessionEditor = (SessionEditor) o; SessionEditorWorkbench workbench = sessionEditor.getSessionWorkbench(); Graph graph = workbench.getGraph(); if (graph.getNumNodes() == 0) { frame.dispose(); } } } }