jdk-24/test/jdk/java/util/Random/T8282144.java

111 lines
3.6 KiB
Java

/*
* Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
import java.util.random.*;
import jdk.internal.util.random.RandomSupport;
/**
* @test
* @summary RandomSupport.convertSeedBytesToLongs sign extension overwrites previous bytes.
* @bug 8282144 8294509
* @modules java.base/jdk.internal.util.random
* @run main T8282144
* @key randomness
*/
public class T8282144 {
public static void main(String[] args) {
testLongs();
testInts();
}
private static void testLongs() {
RandomGenerator rng = RandomGeneratorFactory.of("L64X128MixRandom").create(42);
for (int i = 1; i < 8; i++) {
byte[] seed = new byte[i];
for (int j = 0; j < 10; j++) {
rng.nextBytes(seed);
long[] existing = RandomSupport.convertSeedBytesToLongs(seed, 1, 1);
long[] testing = convertSeedBytesToLongsFixed(seed, 1, 1);
for (int k = 0; k < existing.length; k++) {
if (existing[k] != testing[k]) {
throw new RuntimeException("convertSeedBytesToLongs incorrect");
}
}
}
}
}
private static void testInts() {
RandomGenerator rng = RandomGeneratorFactory.of("L64X128MixRandom").create(42);
for (int i = 1; i < 8; i++) {
byte[] seed = new byte[i];
for (int j = 0; j < 10; j++) {
rng.nextBytes(seed);
int[] existing = RandomSupport.convertSeedBytesToInts(seed, 1, 1);
int[] testing = convertSeedBytesToIntsFixed(seed, 1, 1);
for (int k = 0; k < existing.length; k++) {
if (existing[k] != testing[k]) {
throw new RuntimeException("convertSeedBytesToInts incorrect");
}
}
}
}
}
public static long[] convertSeedBytesToLongsFixed(byte[] seed, int n, int z) {
final long[] result = new long[n];
final int m = Math.min(seed.length, n << 3);
// Distribute seed bytes into the words to be formed.
for (int j = 0; j < m; j++) {
result[j >> 3] = (result[j >> 3] << 8) | (seed[j] & 0xff);
}
return result;
}
public static int[] convertSeedBytesToIntsFixed(byte[] seed, int n, int z) {
final int[] result = new int[n];
final int m = Math.min(seed.length, n << 2);
// Distribute seed bytes into the words to be formed.
for (int j = 0; j < m; j++) {
result[j >> 2] = (result[j >> 2] << 8) | (seed[j] & 0xff);
}
return result;
}
}