@Override
              public boolean done() {
                Entry e = r.getEntry("key");
                if (e == null) {
                  return false;
                }
                return e.getValue() == null;
              }
Test to make sure slow receiver queuing is working

@since GemFire 4.2.1
geode-core/src/distributedTest/java/org/apache/geode/cache30/SlowRecDUnitTest.java