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
   * <p/>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p/>
   * 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.ambari.server.utils;
  
  import java.util.Collections;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.junit.Test;
  
  import junit.framework.Assert;
  
  /**
   * Tests {@link org.apache.ambari.server.utils.SetUtils}
   */
  public class SetUtilsTest {
  
    @Test
    public void testSplit() {
  
      try {
        SetUtils.split(null, 0);
        Assert.fail("Expected IllegalArgumentException.");
      } catch (IllegalArgumentException e) {
        // expected
      }
  
      int size = 10;
      List<Set<Integer>> subsets = SetUtils.split(null, size);
      Assert.assertEquals(0, subsets.size());
  
      subsets = SetUtils.split(Collections.<Integer>emptySet(), size);
      Assert.assertEquals(0, subsets.size());
  
      subsets = SetUtils.split(Collections.singleton(0), size);
      Assert.assertEquals(1, subsets.size());
      Assert.assertEquals(1, subsets.get(0).size());
  
      Set<Integer> set = new LinkedHashSet<>(5);
      for(int i = 0; i < 5; i++) {
        set.add(i);
      }
      subsets = SetUtils.split(set, size);
      Assert.assertEquals(1, subsets.size());
      Assert.assertEquals(5, subsets.get(0).size());
  
  
      set = new LinkedHashSet<>(10);
      for(int i = 0; i < 10; i++) {
        set.add(i);
      }
      subsets = SetUtils.split(set, size);
      Assert.assertEquals(1, subsets.size());
      Assert.assertEquals(10, subsets.get(0).size());
  
      set = new LinkedHashSet<>(11);
      for(int i = 0; i < 11; i++) {
        set.add(i);
      }
      subsets = SetUtils.split(set, size);
      Assert.assertEquals(2, subsets.size());
      Assert.assertEquals(10, subsets.get(0).size());
      Assert.assertEquals(1, subsets.get(1).size());
  
      set = new LinkedHashSet<>(20);
      for(int i = 0; i < 20; i++) {
        set.add(i);
      }
      subsets = SetUtils.split(set, size);
      Assert.assertEquals(2, subsets.size());
      Assert.assertEquals(10, subsets.get(0).size());
      Assert.assertEquals(10, subsets.get(1).size());
  
      set = new LinkedHashSet<>(27);
      for(int i = 0; i < 27; i++) {
        set.add(i);
      }
      subsets = SetUtils.split(set, size);
      Assert.assertEquals(3, subsets.size());
      Assert.assertEquals(10, subsets.get(0).size());
      Assert.assertEquals(10, subsets.get(1).size());
      Assert.assertEquals(7, subsets.get(2).size());
    }
  }
  