question: private boolean remove ( Object o , Object [ ] snapshot , int index ) { final ReentrantLock lock = this . lock ; lock . lock ( ) ; try { Object [ ] current = getArray ( ) ; int len = current . length ; if ( snapshot != current ) findIndex : { int prefix = Math . min ( index , len ) ; for ( int i = 0 ; i < prefix ; i ++ ) { if ( current [ i ] != snapshot [ i ] && eq ( o , current [ i ] ) ) { index = i ; break findIndex ; } } if ( index >= len ) return false ; if ( current [ index ] == o ) break findIndex ; index = indexOf ( o , current , index , len ) ; if ( index < 0 ) return false ; } Object [ ] newElements = new Object [ len - 1 ] ; System . arraycopy ( current , 0 , newElements , 0 , index ) ; System . arraycopy ( current , index + 1 , newElements , index , len - index - 1 ) ; setArray ( newElements ) ; return true ; } finally { lock . unlock ( ) ; } }
target:  A version of remove(Object) using the strong hint that given recent snapshot contains o at the given index.