content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.alibaba.metrics;
  
  import org.junit.Test;
  
  import java.lang.management.ManagementFactory;
  
  import static org.assertj.core.api.Assertions.assertThat;
  import static org.assertj.core.api.Assertions.offset;
  
  public class ClockTest {
      @Test
      public void cpuTimeClock() throws Exception {
          final Clock.CpuTimeClock clock = new Clock.CpuTimeClock();
  
          assertThat((double) clock.getTime())
                  .isEqualTo(System.currentTimeMillis(),
                             offset(100.0));
  
          assertThat((double) clock.getTick())
                     .isEqualTo(ManagementFactory.getThreadMXBean().getCurrentThreadCpuTime(),
                                offset(1000000.0));
      }
  
      @Test
      public void userTimeClock() throws Exception {
          final Clock.UserTimeClock clock = new Clock.UserTimeClock();
  
          assertThat((double) clock.getTime())
                  .isEqualTo(System.currentTimeMillis(),
                             offset(100.0));
  
          assertThat((double) clock.getTick())
                  .isEqualTo(System.nanoTime(),
                             offset(100000.0));
      }
  
      @Test
      public void defaultsToUserTime() throws Exception {
          assertThat(Clock.defaultClock())
                  .isInstanceOf(Clock.UserTimeClock.class);
      }
  }
  