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 org.apache.beam.sdk.transforms;
  
  import java.util.ArrayList;
  import java.util.List;
  import org.apache.beam.sdk.coders.BigEndianIntegerCoder;
  import org.apache.beam.sdk.coders.DoubleCoder;
  import org.apache.beam.sdk.coders.KvCoder;
  import org.apache.beam.sdk.coders.StringUtf8Coder;
  import org.apache.beam.sdk.testing.NeedsRunner;
  import org.apache.beam.sdk.testing.PAssert;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.values.KV;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.TypeDescriptors;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableList;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link MapValues} transform. */
  @RunWith(JUnit4.class)
  public class MapValuesTest {
  
    private static final List<KV<String, Integer>> TABLE =
        ImmutableList.of(KV.of("one", 1), KV.of("two", 2), KV.of("dup", 2));
    private static final List<KV<String, String>> WORDS_TABLE =
        ImmutableList.of(
            KV.of("Length = 3", "one"), KV.of("Length = 4", "three"), KV.of("Length = 0", ""));
  
    private static final List<KV<String, Integer>> EMPTY_TABLE = new ArrayList<>();
    public static final String EXPECTED_FAILURE_MESSAGE = "/ by zero";
  
    @Rule public final TestPipeline p = TestPipeline.create();
  
    @Test
    @Category(NeedsRunner.class)
    public void testMapValuesInto() {
  
      PCollection<KV<String, Integer>> input =
          p.apply(
              Create.of(TABLE)
                  .withCoder(KvCoder.of(StringUtf8Coder.of(), BigEndianIntegerCoder.of())));
  
      PCollection<KV<String, Double>> output =
          input
              .apply(
                  MapValues.into(TypeDescriptors.doubles())
                      .via((SerializableFunction<Integer, Double>) input1 -> input1 * 2d))
              .setCoder(KvCoder.of(StringUtf8Coder.of(), DoubleCoder.of()));
  
      PAssert.that(output)
          .containsInAnyOrder(
              ImmutableList.of(KV.of("one", 2.0d), KV.of("two", 4.0d), KV.of("dup", 4.0d)));
  
      p.run();
    }
  
    @Test
    @Category(NeedsRunner.class)
    public void testMapValuesWithFailures() {
  
      PCollection<KV<String, String>> input =
          p.apply(
              Create.of(WORDS_TABLE)
                  .withCoder(KvCoder.of(StringUtf8Coder.of(), StringUtf8Coder.of())));
  
      WithFailures.Result<PCollection<KV<String, Integer>>, String> result =
          input.apply(
              MapValues.into(TypeDescriptors.integers())
                  .<String, String>via(word -> 1 / word.length())
                  .exceptionsInto(TypeDescriptors.strings())
                  .exceptionsVia(ee -> ee.exception().getMessage()));
      result.output().setCoder(KvCoder.of(StringUtf8Coder.of(), BigEndianIntegerCoder.of()));
  
      PAssert.that(result.output())
          .containsInAnyOrder(ImmutableList.of(KV.of("Length = 3", 0), KV.of("Length = 4", 0)));
      PAssert.that(result.failures()).containsInAnyOrder(EXPECTED_FAILURE_MESSAGE);
  
      p.run();
    }
  
    @Test
    @Category(NeedsRunner.class)
    public void testMapValuesEmpty() {
  
      PCollection<KV<String, Integer>> input =
          p.apply(
              Create.of(EMPTY_TABLE)
                  .withCoder(KvCoder.of(StringUtf8Coder.of(), BigEndianIntegerCoder.of())));
  
      PCollection<KV<String, Double>> output =
          input
              .apply(MapValues.into(TypeDescriptors.doubles()).via(Integer::doubleValue))
              .setCoder(KvCoder.of(StringUtf8Coder.of(), DoubleCoder.of()));
  
      PAssert.that(output).empty();
  
      p.run();
    }
  }
  