/*
    *
    * 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 org.apache.hadoop.hbase.util;
  
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.testclassification.MiscTests;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  import static junit.framework.Assert.assertTrue;
  import static junit.framework.Assert.fail;
  
  /**
   * Tests to make sure that the default environment edge conforms to appropriate
   * behaviour.
   */
  @Category({MiscTests.class, MediumTests.class})
  public class TestDefaultEnvironmentEdge {
  
    @Test
    public void testGetCurrentTimeUsesSystemClock() {
      DefaultEnvironmentEdge edge = new DefaultEnvironmentEdge();
      long systemTime = System.currentTimeMillis();
      long edgeTime = edge.currentTime();
      assertTrue("System time must be either the same or less than the edge time",
              systemTime < edgeTime || systemTime == edgeTime);
      try {
        Thread.sleep(1);
      } catch (InterruptedException e) {
        fail(e.getMessage());
      }
      long secondEdgeTime = edge.currentTime();
      assertTrue("Second time must be greater than the first",
              secondEdgeTime > edgeTime);
    }
  }