public static void getPrefs() throws Exception {
		Preferences sys_prefs = Preferences.systemRoot();
		System.out.println();
		System.out.println("System");
		for(String name : sys_prefs.childrenNames()) {
			printPrefsData(name, sys_prefs);
		}
		
		System.out.println("User");
		Preferences user_prefs = Preferences.userRoot();
		for(String name : user_prefs.childrenNames()) {
			printPrefsData(name, user_prefs);
		}
	}
	public static void printPrefsData(String name, Preferences prefs) throws Exception {
		System.out.println(name);
		Preferences new_prefs = prefs.node(name);
		for(String new_name : new_prefs.childrenNames()) {
			for(String key : new_prefs.keys()) {
				String value = new_prefs.get(key, null);
				System.out.println(key + " : " + value);
			}
			printPrefsData(name + "/" + new_name, prefs);
		}
	}

create or replace procedure getPrefs as language java name 'Test.getPrefs()';

exec getPrefs();