GaugeCellTest.java

/*
 * 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
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 */

package org.apache.beam.runners.core.metrics;

import static org.hamcrest.Matchers.equalTo;
import static org.junit.Assert.assertThat;

import org.apache.beam.sdk.metrics.MetricName;
import org.junit.Test;

/**
 * Tests for {@link GaugeCell}.
 */
public class GaugeCellTest {
  private GaugeCell cell = new GaugeCell(MetricName.named("hello", "world"));

  @Test
  public void testDeltaAndCumulative() {
    cell.set(5);
    cell.set(7);
    assertThat(cell.getCumulative().value(), equalTo(GaugeData.create(7).value()));
    assertThat("getCumulative is idempotent",
        cell.getCumulative().value(), equalTo(7L));

    assertThat(cell.getDirty().beforeCommit(), equalTo(true));
    cell.getDirty().afterCommit();
    assertThat(cell.getDirty().beforeCommit(), equalTo(false));

    cell.set(30);
    assertThat(cell.getCumulative().value(), equalTo(30L));

    assertThat("Adding a new value made the cell dirty",
        cell.getDirty().beforeCommit(), equalTo(true));
  }
}