### Question:
AbstractObservableReader extends AbstractLoggedObservable<ReaderEvent> implements ObservableReader, ProxyReader { public final void removeObserver(ReaderObserver observer) { super.removeObserver(observer); if (super.countObservers() == 0) { logger.debug("Stop the reader monitoring."); stopObservation(); } } protected  AbstractObservableReader(String pluginName, String readerName); final int compareTo(SeReader seReader); final SeResponseSet transmitSet(SeRequestSet requestSet); final SeResponse transmit(SeRequest seRequest); final void addObserver(ReaderObserver observer); final void removeObserver(ReaderObserver observer);  }### Answer:
@Test public void testRemoveObserver() { startObservationCall = new CountDownLatch(5); stopObservationCall = new CountDownLatch(5); spyReader.addObserver(obs1); spyReader.removeObserver(obs1); Assert.assertEquals(0, spyReader.countObservers()); Assert.assertEquals(4, startObservationCall.getCount()); Assert.assertEquals(4, stopObservationCall.getCount()); }