question: protected IObjectInfo < T > store_impl ( Segment < T > segment , ObjectInfo < T > oi ) { if ( _invalid ) return null ; _size . incrementAndGet ( ) ; segment . incrementSize ( ) ; ObjectInfo < T > tail = segment . getTail ( ) ; tail . setForwardRef ( oi ) ; oi . setBackwardRef ( tail ) ; segment . setTail ( oi ) ; return oi ; }
target:  store an element in segment