/** closes resources and write everything to file */
public void shutdown() {
pdb.closeDB(); // save the db
if (newWeights == null) {
newWeights = origWeights;
}
writePropertyFile(
newWeights, genProps.getProperty("outWeightsLoc", genProps.getProperty("inWeightsLoc")));
userInterface.closeResources();
System.out.println("preferences saved and closed without error.");
}