java.util.ResourceBundle

import java.util.Locale;
import java.util.ResourceBundle;

public class TestResourceBundle {
    public static void main(String[] args) {
        ResourceBundle defaultBundle = ResourceBundle.getBundle("mail");
        System.out.println(defaultBundle.getString("message"));

        Locale zhLocale = new Locale("zh", "CN");
        ResourceBundle zhBundle = ResourceBundle.getBundle("mail", zhLocale);
        System.out.println(zhBundle.getString("message"));

        Locale enLocale = new Locale("en", "US");
        ResourceBundle enBundle = ResourceBundle.getBundle("mail", enLocale);
        System.out.println(enBundle.getString("message"));
    }
}