今天装了下正式版的RHEL7,发现熟悉的inittab中没有了改动默认执行级别,打开inittab例如以下 [root@localhost init.d]# vi /etc/inittab # inittab is no longer used when using systemd. # # ADDING CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM. # # Ctrl-Alt-Delete is handled by /etc/sy
object是所有类的基类 如果没有使用extends关键字指明其基类,则默认基类为object类 public class Person{ ........ } 等价于: public class Person extends Object{ ....... } public class TestToString { public static void main(String[] args) { Dog d = new Dog(); System.out.println("d:="