DefaultCounterTest.java

/**
 * Copyright 2015 Netflix, Inc.
 *
 * 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.netflix.spectator.api;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

@RunWith(JUnit4.class)
public class DefaultCounterTest {

  private final ManualClock clock = new ManualClock();

  @Test
  public void testInit() {
    Counter c = new DefaultCounter(clock, NoopId.INSTANCE);
    Assert.assertEquals(c.count(), 0L);
  }

  @Test
  public void testIncrement() {
    Counter c = new DefaultCounter(clock, NoopId.INSTANCE);
    c.increment();
    Assert.assertEquals(c.count(), 1L);
    c.increment();
    c.increment();
    Assert.assertEquals(c.count(), 3L);
  }

  @Test
  public void testIncrementAmount() {
    Counter c = new DefaultCounter(clock, NoopId.INSTANCE);
    c.increment(42);
    Assert.assertEquals(c.count(), 42L);
  }

  @Test
  public void testMeasure() {
    Counter c = new DefaultCounter(clock, NoopId.INSTANCE);
    c.increment(42);
    clock.setWallTime(3712345L);
    for (Measurement m : c.measure()) {
      Assert.assertEquals(m.id(), c.id());
      Assert.assertEquals(m.timestamp(), 3712345L);
      Assert.assertEquals(m.value(), 42.0, 0.1e-12);
    }
  }

}