question: public static void sort ( SortProxy proxy , final long off , final long len ) { if ( len < 7 ) { for ( long i = off ; i < len + off ; i ++ ) { for ( long j = i ; j > off && proxy . compare ( j - 1 , j ) > 0 ; j -- ) { proxy . swap ( j , j - 1 ) ; } } return ; } long m = off + ( len > > 1 ) ; if ( len != 7 ) { long l = off ; long n = off + len - 1 ; if ( len > 40 ) { final long s = len / 8 ; l = med3 ( proxy , l , l + s , l + 2 * s ) ; m = med3 ( proxy , m - s , m , m + s ) ; n = med3 ( proxy , n - 2 * s , n - s , n ) ; } m = med3 ( proxy , l , m , n ) ; } long a = off ; long b = a ; long c = off + len - 1 ; long d = c ; while ( true ) { int bcompm ; while ( b <= c && ( bcompm = proxy . compare ( b , m ) ) <= 0 ) { if ( bcompm == 0 ) { proxy . swap ( a ++ , b ) ; if ( b == m ) { m = a - 1 ; } } b ++ ; } int ccompm ; while ( c >= b && ( ccompm = proxy . compare ( c , m ) ) >= 0 ) { if ( ccompm == 0 ) { proxy . swap ( c , d -- ) ; if ( c == m ) { m = d + 1 ; } } c -- ; } if ( b > c ) { break ; } proxy . swap ( b ++ , c -- ) ; } long s2 ; final long n2 = off + len ; s2 = Math . min ( a - off , b - a ) ; vecswap ( proxy , off , b - s2 , s2 ) ; s2 = Math . min ( d - c , n2 - d - 1 ) ; vecswap ( proxy , b , n2 - s2 , s2 ) ; if ( ( s2 = b - a ) > 1 ) { sort ( proxy , off , s2 ) ; } if ( ( s2 = d - c ) > 1 ) { sort ( proxy , n2 - s2 , s2 ) ; } }
target:  Sorts the specified sub-collection of items through a proxy