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.fn.splittabledofn;
  
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.contains;
  import static org.hamcrest.Matchers.instanceOf;
  import static org.junit.Assert.assertEquals;
  
  import java.util.ArrayList;
  import java.util.List;
  import org.apache.beam.sdk.fn.splittabledofn.RestrictionTrackers.ClaimObserver;
  import org.apache.beam.sdk.transforms.splittabledofn.RestrictionTracker;
  import org.apache.beam.sdk.transforms.splittabledofn.RestrictionTracker.HasProgress;
  import org.apache.beam.sdk.transforms.splittabledofn.SplitResult;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link RestrictionTrackers}. */
  @RunWith(JUnit4.class)
  @SuppressWarnings({
    "rawtypes", // TODO(https://github.com/apache/beam/issues/20447)
  })
  public class RestrictionTrackersTest {
    @Test
    public void testObservingClaims() {
      RestrictionTracker<String, String> observedTracker =
          new RestrictionTracker() {
  
            @Override
            public boolean tryClaim(Object position) {
              return "goodClaim".equals(position);
            }
  
            @Override
            public Object currentRestriction() {
              throw new UnsupportedOperationException();
            }
  
            @Override
            public SplitResult<Object> trySplit(double fractionOfRemainder) {
              throw new UnsupportedOperationException();
            }
  
            @Override
            public void checkDone() throws IllegalStateException {
              throw new UnsupportedOperationException();
            }
  
            @Override
            public IsBounded isBounded() {
              return IsBounded.BOUNDED;
            }
          };
  
      List<String> positionsObserved = new ArrayList<>();
      ClaimObserver<String> observer =
          new ClaimObserver<String>() {
  
            @Override
            public void onClaimed(String position) {
              positionsObserved.add(position);
              assertEquals("goodClaim", position);
            }
  
            @Override
            public void onClaimFailed(String position) {
              positionsObserved.add(position);
            }
          };
  
      RestrictionTracker<String, String> observingTracker =
          RestrictionTrackers.observe(observedTracker, observer);
      observingTracker.tryClaim("goodClaim");
      observingTracker.tryClaim("badClaim");
  
      assertThat(positionsObserved, contains("goodClaim", "badClaim"));
    }
  
    private static class RestrictionTrackerWithProgress extends RestrictionTracker<Object, Object>
        implements HasProgress {
  
      @Override
      public Progress getProgress() {
        return RestrictionTracker.Progress.from(2.0, 3.0);
      }
  
      @Override
      public boolean tryClaim(Object position) {
        return false;
      }
  
      @Override
      public Object currentRestriction() {
        return null;
      }
  
      @Override
      public SplitResult<Object> trySplit(double fractionOfRemainder) {
        return null;
      }
  
      @Override
      public void checkDone() throws IllegalStateException {}
  
      @Override
      public IsBounded isBounded() {
        return IsBounded.BOUNDED;
      }
    }
  
    @Test
    public void testClaimObserversMaintainBacklogInterfaces() {
      RestrictionTracker hasSize =
          RestrictionTrackers.observe(new RestrictionTrackerWithProgress(), null);
      assertThat(hasSize, instanceOf(HasProgress.class));
    }
  }
  