001/*
002 * Copyright (C) 2008 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.google.common.collect.testing;
018
019import static java.util.Arrays.asList;
020
021import com.google.common.annotations.GwtCompatible;
022import com.google.common.collect.testing.features.CollectionSize;
023import java.util.ArrayList;
024import java.util.Collection;
025import java.util.List;
026import org.jspecify.annotations.NullMarked;
027import org.jspecify.annotations.Nullable;
028
029/**
030 * Generator for collection of a particular size.
031 *
032 * @author George van den Driessche
033 */
034@GwtCompatible
035@NullMarked
036public final class OneSizeGenerator<T, E extends @Nullable Object>
037    implements OneSizeTestContainerGenerator<T, E> {
038  private final TestContainerGenerator<T, E> generator;
039  private final CollectionSize collectionSize;
040
041  public OneSizeGenerator(TestContainerGenerator<T, E> generator, CollectionSize collectionSize) {
042    this.generator = generator;
043    this.collectionSize = collectionSize;
044  }
045
046  @Override
047  public TestContainerGenerator<T, E> getInnerGenerator() {
048    return generator;
049  }
050
051  @Override
052  public SampleElements<E> samples() {
053    return generator.samples();
054  }
055
056  @Override
057  public T create(Object... elements) {
058    return generator.create(elements);
059  }
060
061  @Override
062  public E[] createArray(int length) {
063    return generator.createArray(length);
064  }
065
066  @Override
067  public T createTestSubject() {
068    Collection<E> elements = getSampleElements(getCollectionSize().getNumElements());
069    return generator.create(elements.toArray());
070  }
071
072  @Override
073  public Collection<E> getSampleElements(int howMany) {
074    SampleElements<E> samples = samples();
075    List<E> allSampleElements =
076        asList(samples.e0(), samples.e1(), samples.e2(), samples.e3(), samples.e4());
077    return new ArrayList<>(allSampleElements.subList(0, howMany));
078  }
079
080  @Override
081  public CollectionSize getCollectionSize() {
082    return collectionSize;
083  }
084
085  @Override
086  public Iterable<E> order(List<E> insertionOrder) {
087    return generator.order(insertionOrder);
088  }
089}