int getNumValues(RegionEntry entry) {
      Object object = map.get(entry);
      if (object == null) {
        return 0;
      }
      if (object instanceof Collection) {
        Collection coll = (Collection) object;
        return coll.size();
      } else {
        return 1;
      }
    }
We do NOT use any locks here as every remove is for a RegionEntry which is locked before
coming here. No two threads can be entering in this method together for a RegionEntry.
geode-core/src/main/java/org/apache/geode/cache/query/internal/index/AbstractIndex.java