Java How To Program, Late Objects, 11th Edition

... shared by producer and consumer threads
17      private boolean occupied = false; // whether buffer is occupied
18
19      // place int value into buffer
20      @Override
21      public void blockingPut(int value) throws InterruptedException {
22         accessLock.lock(); // lock this object
23
24         // output thread information and buffer information, then wait
25         try {
26            // while buffer is not empty, place thread in waiting state
27            while (occupied) {
28               System.out.println("Producer tries to write.");
29               displayState("Buffer full. Producer waits.");
30               canWrite.await(); // wait until buffer is empty
31            }
32
33            buffer = value; // set new buffer value
34
35            // indicate producer cannot store another value
36            // until consumer retrieves current buffer value
37            occupied = true;  ...