docs: public void setLockingMode( @Nullable final String lockingMode ) {
          if ( lockingMode == null && _lockingMode == null
                  || lockingMode != null && lockingMode.equals( _lockingMode ) ) {
              return;
          }
          _lockingMode = lockingMode;
          if ( _manager.isInitialized() ) {
              initNonStickyLockingMode( createMemcachedNodesManager( _memcachedNodes, _failoverNodes ) );
          }
      }