package org.bouncycastle.util;

General array utilities.
/** * General array utilities. */
public final class Arrays { private Arrays() { // static class, hide constructor } public static boolean areEqual( boolean[] a, boolean[] b) { if (a == b) { return true; } if (a == null || b == null) { return false; } if (a.length != b.length) { return false; } for (int i = 0; i != a.length; i++) { if (a[i] != b[i]) { return false; } } return true; } public static boolean areEqual( char[] a, char[] b) { if (a == b) { return true; } if (a == null || b == null) { return false; } if (a.length != b.length) { return false; } for (int i = 0; i != a.length; i++) { if (a[i] != b[i]) { return false; } } return true; } public static boolean areEqual( byte[] a, byte[] b) { if (a == b) { return true; } if (a == null || b == null) { return false; } if (a.length != b.length) { return false; } for (int i = 0; i != a.length; i++) { if (a[i] != b[i]) { return false; } } return true; }
A constant time equals comparison - does not terminate early if test will fail.
Params:
  • a – first array
  • b – second array
Returns:true if arrays equal, false otherwise.
/** * A constant time equals comparison - does not terminate early if * test will fail. * * @param a first array * @param b second array * @return true if arrays equal, false otherwise. */
public static boolean constantTimeAreEqual( byte[] a, byte[] b) { if (a == b) { return true; } if (a == null || b == null) { return false; } if (a.length != b.length) { return false; } int nonEqual = 0; for (int i = 0; i != a.length; i++) { nonEqual |= (a[i] ^ b[i]); } return nonEqual == 0; } public static boolean areEqual( int[] a, int[] b) { if (a == b) { return true; } if (a == null || b == null) { return false; } if (a.length != b.length) { return false; } for (int i = 0; i != a.length; i++) { if (a[i] != b[i]) { return false; } } return true; } public static void fill( byte[] array, byte value) { for (int i = 0; i < array.length; i++) { array[i] = value; } } public static void fill( long[] array, long value) { for (int i = 0; i < array.length; i++) { array[i] = value; } } public static void fill( short[] array, short value) { for (int i = 0; i < array.length; i++) { array[i] = value; } } public static int hashCode(byte[] data) { if (data == null) { return 0; } int i = data.length; int hc = i + 1; while (--i >= 0) { hc *= 257; hc ^= data[i]; } return hc; } public static byte[] clone(byte[] data) { if (data == null) { return null; } byte[] copy = new byte[data.length]; System.arraycopy(data, 0, copy, 0, data.length); return copy; } public static int[] clone(int[] data) { if (data == null) { return null; } int[] copy = new int[data.length]; System.arraycopy(data, 0, copy, 0, data.length); return copy; } }