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Library for use in Java components of Vespa. Shared code which do
not fit anywhere else.
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.collections;
/**
* Utility class which is useful when implementing Comparable and one needs to
* compare byte arrays as instance variables.
*
* @author Einar M R Rosenvinge
*/
public class ByteArrayComparator {
/**
* Compare the arguments. Shorter arrays are always considered
* smaller than longer arrays. For arrays of equal lengths, the elements
* are compared one-by-one. Whenever two corresponding elements in the
* two arrays are non-equal, the method returns. If all elements at
* corresponding positions in the two arrays are equal, the arrays
* are considered equal.
*
* @param first a byte array to be compared
* @param second a byte array to be compared
* @return 0 if the arguments are equal, -1 if the first argument is smaller, 1 if the second argument is smaller
* @throws NullPointerException if any of the arguments are null
*/
public static int compare(byte[] first, byte[] second) {
if (first.length < second.length) {
return -1;
}
if (first.length > second.length) {
return 1;
}
// lengths are equal, compare contents
for (int i = 0; i < first.length; i++) {
if (first[i] < second[i]) {
return -1;
} else if (first[i] > second[i]) {
return 1;
}
// values at index i are equal, continue...
}
// we haven't returned yet; contents must be equal:
return 0;
}
}