question: public HeldLocksGrant ( BigInteger grantId ) { this . grantId = Preconditions . checkNotNull ( grantId ) ; creationDateMs = System . currentTimeMillis ( ) ; expirationDateMs = - 1 ; lockMap = LockCollections . of ( ) ; lockTimeout = null ; versionId = null ; }
target:  These grants should not be constructed by users.  Only the lock service should hand them out.