| /* |
| * Copyright (C) 2020 The Android Open Source Project |
| * |
| * Licensed 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 |
| * |
| * http://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 com.google.android.exoplayer2.util; |
| |
| import static com.google.common.truth.Truth.assertThat; |
| import static org.junit.Assert.assertThrows; |
| |
| import androidx.test.ext.junit.runners.AndroidJUnit4; |
| import java.util.Iterator; |
| import java.util.Set; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| |
| /** Tests for {@link CopyOnWriteMultiset}. */ |
| @RunWith(AndroidJUnit4.class) |
| public final class CopyOnWriteMultisetTest { |
| |
| @Test |
| public void multipleEqualObjectsCountedAsExpected() { |
| String item1 = "a string"; |
| String item2 = "a string"; |
| String item3 = "different string"; |
| |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| |
| multiset.add(item1); |
| multiset.add(item2); |
| multiset.add(item3); |
| |
| assertThat(multiset).containsExactly("a string", "a string", "different string"); |
| assertThat(multiset.elementSet()).containsExactly("a string", "different string"); |
| } |
| |
| @Test |
| public void removingObjectDecrementsCount() { |
| String item1 = "a string"; |
| String item2 = "a string"; |
| String item3 = "different string"; |
| |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| |
| multiset.add(item1); |
| multiset.add(item2); |
| multiset.add(item3); |
| |
| multiset.remove("a string"); |
| |
| assertThat(multiset).containsExactly("a string", "different string"); |
| assertThat(multiset.elementSet()).containsExactly("a string", "different string"); |
| } |
| |
| @Test |
| public void removingLastObjectRemovesCompletely() { |
| String item1 = "a string"; |
| String item2 = "a string"; |
| String item3 = "different string"; |
| |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| |
| multiset.add(item1); |
| multiset.add(item2); |
| multiset.add(item3); |
| |
| multiset.remove("different string"); |
| |
| assertThat(multiset).containsExactly("a string", "a string"); |
| assertThat(multiset.elementSet()).containsExactly("a string"); |
| } |
| |
| @Test |
| public void removingNonexistentElementSucceeds() { |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| |
| multiset.remove("a string"); |
| } |
| |
| @Test |
| public void modifyingIteratorFails() { |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| multiset.add("a string"); |
| |
| Iterator<String> iterator = multiset.iterator(); |
| |
| assertThrows(UnsupportedOperationException.class, iterator::remove); |
| } |
| |
| @Test |
| public void modifyingElementSetFails() { |
| CopyOnWriteMultiset<String> multiset = new CopyOnWriteMultiset<>(); |
| multiset.add("a string"); |
| |
| Set<String> elementSet = multiset.elementSet(); |
| |
| assertThrows(UnsupportedOperationException.class, () -> elementSet.remove("a string")); |
| } |
| } |