/*
* SonarQube
* Copyright (C) 2009-2017 SonarSource SA
* mailto:info AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This program 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.core.util;
import java.util.ArrayList;
import java.util.Base64;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.concurrent.atomic.AtomicInteger;
import org.junit.Test;
import static org.assertj.core.api.Assertions.assertThat;
public class UuidGeneratorImplTest {
private UuidGeneratorImpl underTest = new UuidGeneratorImpl();
@Test
public void generate_returns_unique_values_without_common_initial_letter_given_more_than_one_millisecond_between_generate_calls() throws InterruptedException {
Base64.Encoder encoder = Base64.getEncoder();
int count = 30;
Set<String> uuids = new HashSet<>(count);
for (int i = 0; i < count; i++) {
Thread.sleep(5);
uuids.add(encoder.encodeToString(underTest.generate()));
}
assertThat(uuids).hasSize(count);
Iterator<String> iterator = uuids.iterator();
String firstUuid = iterator.next();
String base = firstUuid.substring(0, firstUuid.length() - 4);
for (int i = 1; i < count; i++) {
assertThat(iterator.next()).describedAs("i=" + i).doesNotStartWith(base);
}
}
@Test
public void generate_concurrent_test() throws InterruptedException {
int rounds = 500;
List<byte[]> uuids1 = new ArrayList<>(rounds);
List<byte[]> uuids2 = new ArrayList<>(rounds);
Thread t1 = new Thread(() -> {
for (int i = 0; i < rounds; i++) {
uuids1.add(underTest.generate());
}
});
Thread t2 = new Thread(() -> {
for (int i = 0; i < rounds; i++) {
uuids2.add(underTest.generate());
}
});
t1.start();
t2.start();
t1.join();
t2.join();
Base64.Encoder encoder = Base64.getEncoder();
Set<String> uuids = new HashSet<>(rounds * 2);
uuids1.forEach(bytes -> uuids.add(encoder.encodeToString(bytes)));
uuids2.forEach(bytes -> uuids.add(encoder.encodeToString(bytes)));
assertThat(uuids).hasSize(rounds * 2);
}
@Test
public void generate_from_FixedBase_returns_unique_values_where_only_last_4_later_letter_change() {
Base64.Encoder encoder = Base64.getEncoder();
int count = 100_000;
Set<String> uuids = new HashSet<>(count);
UuidGenerator.WithFixedBase withFixedBase = underTest.withFixedBase();
for (int i = 0; i < count; i++) {
uuids.add(encoder.encodeToString(withFixedBase.generate(i)));
}
assertThat(uuids).hasSize(count);
Iterator<String> iterator = uuids.iterator();
String firstUuid = iterator.next();
String base = firstUuid.substring(0, firstUuid.length() - 4);
while (iterator.hasNext()) {
assertThat(iterator.next()).startsWith(base);
}
}
@Test
public void generate_from_FixedBase_concurrent_test() throws InterruptedException {
UuidGenerator.WithFixedBase withFixedBase = underTest.withFixedBase();
int rounds = 500;
List<byte[]> uuids1 = new ArrayList<>(rounds);
List<byte[]> uuids2 = new ArrayList<>(rounds);
AtomicInteger cnt = new AtomicInteger();
Thread t1 = new Thread(() -> {
for (int i = 0; i < rounds; i++) {
uuids1.add(withFixedBase.generate(cnt.getAndIncrement()));
}
});
Thread t2 = new Thread(() -> {
for (int i = 0; i < rounds; i++) {
uuids2.add(withFixedBase.generate(cnt.getAndIncrement()));
}
});
t1.start();
t2.start();
t1.join();
t2.join();
Base64.Encoder encoder = Base64.getEncoder();
Set<String> uuids = new HashSet<>(rounds * 2);
uuids1.forEach(bytes -> uuids.add(encoder.encodeToString(bytes)));
uuids2.forEach(bytes -> uuids.add(encoder.encodeToString(bytes)));
assertThat(uuids).hasSize(rounds * 2);
}
}