docs: public boolean add( T entry ) {
          assert entry != null;
          if (!addEntries.get()) return false;
          try {
              producerLock.lock();
              long position = cursor.claim(); // blocks; if this fails, we will not have successfully claimed and nothing to do ...
              int index = (int)(position & mask);
              buffer[index] = entry;
              return cursor.publish(position);
          } finally {
              producerLock.unlock();
          }
      }