void (@Nullable final DataNode<ProjectData> externalProject) { if (externalProject == null) { System.err.println("Got null External project after import"); return; } try { ProjectDataManager.getInstance().importData(externalProject, myProject); } catch (Throwable ex) { ex.printStackTrace(System.err); error.set(Couple.of("Exception occurred in `ProjectDataManager.importData` (see output for the details)", null)); } System.out.println("External project was successfully imported"); }