Java™ How To Program (Early Objects), Tenth Edition

Class SynchronizedBuffer

Class SynchronizedBuffer (Fig. 23.20) contains five fields. Line 11 creates a new object of type ReentrantLock and assigns its reference to Lock variable accessLock. The ReentrantLock is created without the fairness policy because at any time only a single Producer or Consumer will be waiting to acquire the Lock in this example. Lines 14–15 create two Conditions using Lock method newCondition. Condition canWrite contains a queue for a Producer thread waiting while the buffer is full (i.e., there’s data in the buffer that the Consumer has not read yet). If the buffer is full, the Producer calls method await on this Condition. When the Consumer reads data from a full buffer, it calls method signal on this Condition. ...