public void setCustomEntryTimeToLive(CustomExpiry<K, V> custom) {
    regionAttributes.customEntryTimeToLive = custom;
    regionAttributes.setHasCustomEntryTimeToLive(true);
  }
Sets the custom timeToLive for the next {@code RegionAttributes} created.

@param custom the CustomExpiry to use, none if the default for the region is to be used.
geode-core/src/main/java/org/apache/geode/cache/AttributesFactory.java