src/test/java/com/google/devtools/build/lib/concurrent/FastHotKeyAtomicLongMapTest.java

// Copyright 2018 The Bazel Authors. All rights reserved.
//
// 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.devtools.build.lib.concurrent;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSortedMap;
import java.util.concurrent.atomic.AtomicLong;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Very basic tests for {@link FastHotKeyAtomicLongMap}. */
@RunWith(JUnit4.class)
public class FastHotKeyAtomicLongMapTest {
  @Test
  public void simple() {
    FastHotKeyAtomicLongMap<String> map = FastHotKeyAtomicLongMap.create();
    assertThat(map.asImmutableMap()).isEmpty();
    AtomicLong catAtomicLong = map.getCounter("cat");
    assertThat(catAtomicLong.get()).isEqualTo(0L);
    assertThat(map.incrementAndGet("cat")).isEqualTo(1L);
    assertThat(catAtomicLong.get()).isEqualTo(1L);
    assertThat(catAtomicLong.incrementAndGet()).isEqualTo(2L);
    assertThat(map.incrementAndGet("dog")).isEqualTo(1L);
    assertThat(ImmutableSortedMap.copyOf(map.asImmutableMap())).isEqualTo(
        ImmutableMap.of("cat", 2L, "dog", 1L));
    assertThat(map.incrementAndGet("cat")).isEqualTo(3L);
    assertThat(ImmutableSortedMap.copyOf(map.asImmutableMap())).isEqualTo(
        ImmutableMap.of("cat", 3L, "dog", 1L));
    assertThat(map.decrementAndGet("cat")).isEqualTo(2L);
    assertThat(catAtomicLong.decrementAndGet()).isEqualTo(1L);
    assertThat(map.decrementAndGet("dog")).isEqualTo(0L);
    assertThat(map.decrementAndGet("cat")).isEqualTo(0L);
    assertThat(ImmutableSortedMap.copyOf(map.asImmutableMap())).isEqualTo(
        ImmutableMap.of("cat", 0L, "dog", 0L));
    map.clear();
    assertThat(map.asImmutableMap()).isEmpty();
  }
}