public Set<PartitionId> getPartitionSet() {
      return partitionSet;
    }
Check if two collections have same contents.
@param collection1 {@link Collection} object to compare.
@param collection2 {@link Collection} object to compare.
@return true if contents are equals. false otherwise.
ambry-vcr/src/test/java/com/github/ambry/vcr/HelixVcrClusterParticipantTest.java