@Override
  public boolean isDestroyed() {
    if (entryIsDestroyed) {
      return true;
    }
    if (region.isThisRegionBeingClosedOrDestroyed() || region.basicGetEntry(key) == null) {
      entryIsDestroyed = true;
      return true;
    }
    return false;
  }
Internal method for getting the underlying RegionEntry
geode-core/src/main/java/org/apache/geode/internal/cache/NonTXEntry.java