The most effective method for deciding if a schedule is serializable is Two-phase locking protocol. 判断一个调度是否可串行化调度的最有效方法是两段锁协议。
If a class that is designed for inheritance is not serializable, it may be impossible to write a serializable subclass. 如果一个专门为了继承而设计的类不是可序列化的，那么要编写出可系列化的子类几乎是不可能的。
