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.kafka.common.utils;
  
  import org.junit.jupiter.api.Test;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.function.Function;
  import java.util.stream.Collectors;
  
  import static java.util.Arrays.asList;
  import static java.util.Collections.emptyList;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  
  public class MappedIteratorTest {
  
      @Test
      public void testStringToInteger() {
          List<String> list = asList("foo", "", "bar2", "baz45");
          Function<String, Integer> mapper = String::length;
  
          Iterable<Integer> mappedIterable = () -> new MappedIterator<>(list.iterator(), mapper);
          List<Integer> mapped = new ArrayList<>();
          mappedIterable.forEach(mapped::add);
  
          assertEquals(list.stream().map(mapper).collect(Collectors.toList()), mapped);
  
          // Ensure that we can iterate a second time
          List<Integer> mapped2 = new ArrayList<>();
          mappedIterable.forEach(mapped2::add);
          assertEquals(mapped, mapped2);
      }
  
      @Test
      public void testEmptyList() {
          List<String> list = emptyList();
          Function<String, Integer> mapper = String::length;
  
          Iterable<Integer> mappedIterable = () -> new MappedIterator<>(list.iterator(), mapper);
          List<Integer> mapped = new ArrayList<>();
          mappedIterable.forEach(mapped::add);
  
          assertEquals(emptyList(), mapped);
      }
  
  }
  