@Test
  public void testRegisterInterest_Destroy_Concurrent() throws Exception {
    PoolImpl.BEFORE_REGISTER_CALLBACK_FLAG = true;
    ClientServerObserverHolder.setInstance(new ClientServerObserverAdapter() {
      @Override
      public void beforeInterestRegistration() {
        Region r = cache.getRegion(SEPARATOR + REGION_NAME);
        r.put(KEY, "AgainDummyValue");
        r.destroy(KEY);
        PoolImpl.BEFORE_REGISTER_CALLBACK_FLAG = false;
      }
    });

    Region r = cache.getRegion(SEPARATOR + REGION_NAME);
    r.put(KEY, "DummyValue");
    server1.invoke(() -> DurableResponseMatrixDUnitTest.updateEntry(KEY, "ValueMatrix1"));

    r.registerInterest(KEY, InterestResultPolicy.KEYS_VALUES);
    assertEquals(null, r.getEntry(KEY));
  }
Tests that the Matris defined in <code>ServerResponseMatrix</code> is applied or not

@since GemFire 5.1
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/DurableResponseMatrixDUnitTest.java