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* Licensed to the Apache Software Foundation (ASF) under one
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* 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.flink.runtime.operators.sort;
import java.util.ArrayList;
import java.util.List;
import org.apache.flink.api.common.typeutils.TypeComparator;
import org.apache.flink.api.common.typeutils.base.IntComparator;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.runtime.operators.testutils.TestData;
import org.apache.flink.util.MutableObjectIterator;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
public class MergeIteratorTest {
private TypeComparator<Tuple2<Integer, String>> comparator;
@SuppressWarnings("unchecked")
@Before
public void setup() {
this.comparator = TestData.getIntStringTupleComparator();
}
private MutableObjectIterator<Tuple2<Integer, String>> newIterator(final int[] keys, final String[] values) {
return new MutableObjectIterator<Tuple2<Integer, String>>() {
private int key = 0;
private String value = new String();
private int current = 0;
@Override
public Tuple2<Integer, String> next(Tuple2<Integer, String> reuse) {
if (current < keys.length) {
key = keys[current];
value = values[current];
current++;
reuse.setField(key, 0);
reuse.setField(value, 1);
return reuse;
}
else {
return null;
}
}
@Override
public Tuple2<Integer, String> next() {
if (current < keys.length) {
Tuple2<Integer, String> result = new Tuple2<>(keys[current], values[current]);
current++;
return result;
}
else {
return null;
}
}
};
}
@Test
public void testMergeOfTwoStreams() throws Exception
{
// iterators
List<MutableObjectIterator<Tuple2<Integer, String>>> iterators = new ArrayList<>();
iterators.add(newIterator(new int[] { 1, 2, 4, 5, 10 }, new String[] { "1", "2", "4", "5", "10" }));
iterators.add(newIterator(new int[] { 3, 6, 7, 10, 12 }, new String[] { "3", "6", "7", "10", "12" }));
final int[] expected = new int[] {1, 2, 3, 4, 5, 6, 7, 10, 10, 12};
// comparator
TypeComparator<Integer> comparator = new IntComparator(true);
// merge iterator
MutableObjectIterator<Tuple2<Integer, String>> iterator = new MergeIterator<>(iterators, this.comparator);
// check expected order
Tuple2<Integer, String> rec1 = new Tuple2<>();
Tuple2<Integer, String> rec2 = new Tuple2<>();
int k1 = 0;
int k2 = 0;
int pos = 1;
Assert.assertTrue((rec1 = iterator.next(rec1)) != null);
Assert.assertEquals(expected[0], rec1.f0.intValue());
while ((rec2 = iterator.next(rec2)) != null) {
k1 = rec1.f0;
k2 = rec2.f0;
Assert.assertTrue(comparator.compare(k1, k2) <= 0);
Assert.assertEquals(expected[pos++], k2);
Tuple2<Integer, String> tmp = rec1;
rec1 = rec2;
rec2 = tmp;
}
}
@Test
public void testMergeOfTenStreams() throws Exception
{
// iterators
List<MutableObjectIterator<Tuple2<Integer, String>>> iterators = new ArrayList<>();
iterators.add(newIterator(new int[] { 1, 2, 17, 23, 23 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 2, 6, 7, 8, 9 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 4, 10, 11, 11, 12 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 3, 6, 7, 10, 12 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 7, 10, 15, 19, 44 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 6, 6, 11, 17, 18 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 1, 2, 4, 5, 10 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 5, 10, 19, 23, 29 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 9, 9, 9, 9, 9 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 8, 8, 14, 14, 15 }, new String[] { "A", "B", "C", "D", "E" }));
// comparator
TypeComparator<Integer> comparator = new IntComparator(true);
// merge iterator
MutableObjectIterator<Tuple2<Integer, String>> iterator = new MergeIterator<>(iterators, this.comparator);
int elementsFound = 1;
// check expected order
Tuple2<Integer, String> rec1 = new Tuple2<>();
Tuple2<Integer, String> rec2 = new Tuple2<>();
Assert.assertTrue((rec1 = iterator.next(rec1)) != null);
while ((rec2 = iterator.next(rec2)) != null) {
elementsFound++;
Assert.assertTrue(comparator.compare(rec1.f0, rec2.f0) <= 0);
Tuple2<Integer, String> tmp = rec1;
rec1 = rec2;
rec2 = tmp;
}
Assert.assertEquals("Too few elements returned from stream.", 50, elementsFound);
}
@Test
public void testInvalidMerge() throws Exception
{
// iterators
List<MutableObjectIterator<Tuple2<Integer, String>>> iterators = new ArrayList<>();
iterators.add(newIterator(new int[] { 1, 2, 17, 23, 23 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 2, 6, 7, 8, 9 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 4, 10, 11, 11, 12 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 3, 6, 10, 7, 12 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 7, 10, 15, 19, 44 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 6, 6, 11, 17, 18 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 1, 2, 4, 5, 10 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 5, 10, 19, 23, 29 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 9, 9, 9, 9, 9 }, new String[] { "A", "B", "C", "D", "E" }));
iterators.add(newIterator(new int[] { 8, 8, 14, 14, 15 }, new String[] { "A", "B", "C", "D", "E" }));
// comparator
TypeComparator<Integer> comparator = new IntComparator(true);
// merge iterator
MutableObjectIterator<Tuple2<Integer, String>> iterator = new MergeIterator<>(iterators, this.comparator);
boolean violationFound = false;
// check expected order
Tuple2<Integer, String> rec1 = new Tuple2<>();
Tuple2<Integer, String> rec2 = new Tuple2<>();
Assert.assertTrue((rec1 = iterator.next(rec1)) != null);
while ((rec2 = iterator.next(rec2)) != null)
{
if (comparator.compare(rec1.f0, rec2.f0) > 0) {
violationFound = true;
break;
}
Tuple2<Integer, String> tmp = rec1;
rec1 = rec2;
rec2 = tmp;
}
Assert.assertTrue("Merge must have returned a wrong result", violationFound);
}
}