src/test/java/org/apache/datasketches/frequencies/SerDeCompatibilityTest.java

/*
 * 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
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 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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 */

package org.apache.datasketches.frequencies;

import org.testng.Assert;
import org.testng.annotations.Test;

import org.apache.datasketches.memory.WritableMemory;
import org.apache.datasketches.ArrayOfItemsSerDe;
import org.apache.datasketches.ArrayOfLongsSerDe;

@SuppressWarnings("javadoc")
public class SerDeCompatibilityTest {

  static final ArrayOfItemsSerDe<Long> serDe = new ArrayOfLongsSerDe();

  @Test
  public void itemsToLongs() {
    ItemsSketch<Long> sketch1 = new ItemsSketch<>(8);
    sketch1.update(1L);
    sketch1.update(2L);
    sketch1.update(3L);
    sketch1.update(4L);

    byte[] bytes = sketch1.toByteArray(serDe);
    LongsSketch sketch2 = LongsSketch.getInstance(WritableMemory.writableWrap(bytes));
    sketch2.update(2L);
    sketch2.update(3L);
    sketch2.update(2L);

    Assert.assertFalse(sketch2.isEmpty());
    Assert.assertEquals(sketch2.getNumActiveItems(), 4);
    Assert.assertEquals(sketch2.getStreamLength(), 7);
    Assert.assertEquals(sketch2.getEstimate(1L), 1);
    Assert.assertEquals(sketch2.getEstimate(2L), 3);
    Assert.assertEquals(sketch2.getEstimate(3L), 2);
    Assert.assertEquals(sketch2.getEstimate(4L), 1);
  }

  @Test
  public void longsToItems() {
    LongsSketch sketch1 = new LongsSketch(8);
    sketch1.update(1L);
    sketch1.update(2L);
    sketch1.update(3L);
    sketch1.update(4L);

    byte[] bytes = sketch1.toByteArray();
    ItemsSketch<Long> sketch2 = ItemsSketch.getInstance(WritableMemory.writableWrap(bytes), serDe);
    sketch2.update(2L);
    sketch2.update(3L);
    sketch2.update(2L);

    Assert.assertFalse(sketch2.isEmpty());
    Assert.assertEquals(sketch2.getNumActiveItems(), 4);
    Assert.assertEquals(sketch2.getStreamLength(), 7);
    Assert.assertEquals(sketch2.getEstimate(1L), 1);
    Assert.assertEquals(sketch2.getEstimate(2L), 3);
    Assert.assertEquals(sketch2.getEstimate(3L), 2);
    Assert.assertEquals(sketch2.getEstimate(4L), 1);
  }

  @Test
  public void checkInsertSerDeId() {
    long pre0 = 0L;
    pre0 = PreambleUtil.insertSerDeId((short) -1, pre0);
    short serDeId = PreambleUtil.extractSerDeId(pre0);
    Assert.assertEquals(serDeId, -1);
  }
}