| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * https://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.trevni; |
| |
| import java.util.Random; |
| |
| import java.nio.ByteBuffer; |
| |
| import org.junit.Assert; |
| import org.junit.Test; |
| |
| public class TestUtil { |
| |
| private static long seed; |
| private static boolean seedSet; |
| |
| /** |
| * Returns the random seed for this test run. By default uses the current time, |
| * but a test run can be replicated by specifying the "test.seed" system |
| * property. The seed is printed the first time it's accessed so that failures |
| * can be replicated if needed. |
| */ |
| public static long getRandomSeed() { |
| if (!seedSet) { |
| String configured = System.getProperty("test.seed"); |
| if (configured != null) |
| seed = Long.valueOf(configured); |
| else |
| seed = System.currentTimeMillis(); |
| System.err.println("test.seed=" + seed); |
| seedSet = true; |
| } |
| return seed; |
| } |
| |
| public static void resetRandomSeed() { |
| seedSet = false; |
| } |
| |
| public static Random createRandom() { |
| return new Random(getRandomSeed()); |
| } |
| |
| public static ByteBuffer randomBytes(Random random) { |
| byte[] bytes = new byte[randomLength(random)]; |
| random.nextBytes(bytes); |
| return ByteBuffer.wrap(bytes); |
| } |
| |
| public static String randomString(Random random) { |
| int length = randomLength(random); |
| char[] chars = new char[length]; |
| for (int i = 0; i < length; i++) |
| chars[i] = (char) ('a' + random.nextInt('z' - 'a')); |
| return new String(chars); |
| } |
| |
| /** |
| * Returns [0-15] 15/16 times. Returns [0-255] 255/256 times. Returns [0-4095] |
| * 4095/4096 times. Returns [0-65535] every time. |
| */ |
| public static int randomLength(Random random) { |
| int n = random.nextInt(); |
| if (n < 0) |
| n = -n; |
| return n & ((n & 0xF0000) != 0 ? 0xF : ((n & 0xFF0000) != 0 ? 0xFF : ((n & 0xFFF0000) != 0 ? 0xFFF : 0xFFFF))); |
| } |
| |
| @Test |
| public void testRandomLength() { |
| long total = 0; |
| int count = 1024 * 1024; |
| int min = Short.MAX_VALUE; |
| int max = 0; |
| Random r = createRandom(); |
| for (int i = 0; i < count; i++) { |
| int length = randomLength(r); |
| if (min > length) |
| min = length; |
| if (max < length) |
| max = length; |
| total += length; |
| } |
| Assert.assertEquals(0, min); |
| Assert.assertTrue(max > 1024 * 32); |
| |
| float average = total / (float) count; |
| Assert.assertTrue(average > 16.0f); |
| Assert.assertTrue(average < 64.0f); |
| |
| } |
| |
| } |