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.Arrays;
  import org.apache.beam.sdk.testing.PAssert;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.testing.UsesImpulse;
  import org.apache.beam.sdk.testing.ValidatesRunner;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.TypeDescriptors;
  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 Impulse. */
  @RunWith(JUnit4.class)
  public class ImpulseTest {
    @Rule public transient TestPipeline p = TestPipeline.create();
  
    @Test
    @Category({ValidatesRunner.class, UsesImpulse.class})
    public void testImpulse() {
      PCollection<Integer> result =
          p.apply(Impulse.create())
              .apply(
                  FlatMapElements.into(TypeDescriptors.integers())
                      .via(impulse -> Arrays.asList(1, 2, 3)));
      PAssert.that(result).containsInAnyOrder(1, 2, 3);
      p.run().waitUntilFinish();
    }
  }
  