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.
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  package org.apache.beam.runners.dataflow.worker;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertTrue;
  import static org.mockito.ArgumentMatchers.any;
  import static org.mockito.Mockito.when;
  
  import com.google.api.services.dataflow.model.SideInputInfo;
  import java.util.concurrent.atomic.AtomicInteger;
  import org.apache.beam.runners.core.SideInputReader;
  import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
  import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
  import org.apache.beam.sdk.values.PCollectionView;
  import org.apache.beam.sdk.values.TupleTag;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableList;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  import org.mockito.Mock;
  import org.mockito.MockitoAnnotations;
  
  /** Tests for {@link LazilyInitializedSideInputReader}. */
  @RunWith(JUnit4.class)
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
  })
  public class LazilyInitializedSideInputReaderTest {
    private static final String TEST_TAG = "test_tag";
  
    @Mock private SideInputReader mockSideInputReader;
    @Mock private PCollectionView mockPCollectionView;
  
    @Before
    public void setUp() {
      MockitoAnnotations.initMocks(this);
    }
  
    @Test
    public void testLazyInitialization() {
      final AtomicInteger wasCalled = new AtomicInteger();
      SideInputReader lazilyInitializedSideInputReader =
          new LazilyInitializedSideInputReader(
              ImmutableList.of(new SideInputInfo().setTag(TEST_TAG)),
              () -> {
                wasCalled.incrementAndGet();
                return mockSideInputReader;
              });
      // Ensure that after construction we have not been initialized yet.
      assertEquals(0, wasCalled.get());
  
      // Ensure that after checking some basic tag information we have not been initialized yet.
      assertFalse(lazilyInitializedSideInputReader.isEmpty());
      assertEquals(0, wasCalled.get());
  
      when(mockPCollectionView.getTagInternal()).thenReturn(new TupleTag(TEST_TAG));
      assertTrue(lazilyInitializedSideInputReader.contains(mockPCollectionView));
      assertEquals(0, wasCalled.get());
  
      // Ensure that we were constructed only once, and provided the expected parameters and returned
      // the expected result.
      when(mockSideInputReader.get(any(PCollectionView.class), any(BoundedWindow.class)))
          .thenReturn(42)
          .thenReturn(43);
      assertEquals(
          42, lazilyInitializedSideInputReader.get(mockPCollectionView, GlobalWindow.INSTANCE));
      assertEquals(1, wasCalled.get());
      assertEquals(
          43, lazilyInitializedSideInputReader.get(mockPCollectionView, GlobalWindow.INSTANCE));
      assertEquals(1, wasCalled.get());
    }
  }
  