001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.metrics.impl;
019
020import static org.junit.jupiter.api.Assertions.assertEquals;
021
022import java.util.concurrent.atomic.AtomicLong;
023import org.apache.hadoop.hbase.metrics.Gauge;
024import org.apache.hadoop.hbase.testclassification.SmallTests;
025import org.junit.jupiter.api.Tag;
026import org.junit.jupiter.api.Test;
027
028/**
029 * Test class for {@link Gauge}.
030 */
031@Tag(SmallTests.TAG)
032public class TestGauge {
033
034  @Test
035  public void testGetValue() {
036    SimpleGauge gauge = new SimpleGauge();
037    assertEquals(0, (long) gauge.getValue());
038
039    gauge.setValue(1000L);
040    assertEquals(1000L, (long) gauge.getValue());
041  }
042
043  /**
044   * Gauge implementation with a setter.
045   */
046  private static class SimpleGauge implements Gauge<Long> {
047
048    private final AtomicLong value = new AtomicLong(0L);
049
050    @Override
051    public Long getValue() {
052      return this.value.get();
053    }
054
055    public void setValue(long value) {
056      this.value.set(value);
057    }
058  }
059}