/**
* 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());
}
}