1 package jdk.jfr.internal.util;

     2 

     3 import java.util.Random;

     4 

     5 public class UniversalHashFamily {

     6     final Random rand = new Random();

     7 

     8     private static long getA(long hashFunction) {

     9         return hashFunction | 1;

    10     }

    11 

    12     private static long getB(long hashFunction, long mask) {

    13         return hashFunction & mask;

    14     }

    15 

    16     private static long getHash(long key, long hashFunction, long mask) {

    17         return (getA(hashFunction) * key) + (hashFunction & mask);

    18     }

    19 

    20     public static int getIndex(long key, long hashFunction, long shift, long mask) {

    21         return (int)(getHash(key, hashFunction, mask) >>> shift);

    22     }

    23 

    24     public long getRandomHashFunction() {

    25         return rand.nextLong() & Long.MAX_VALUE;

    26     }

    27 }