uk.gov.gchq.gaffer.sketches.datasketches.cardinality.serialisation.HllSketchSerialiser Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of sketches-library Show documentation

There is a newer version: 2.3.1

/*
 * Copyright 2017-2023 Crown Copyright
 *
 * Licensed 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 uk.gov.gchq.gaffer.sketches.datasketches.cardinality.serialisation;

import org.apache.datasketches.hll.HllSketch;

import uk.gov.gchq.gaffer.exception.SerialisationException;
import uk.gov.gchq.gaffer.serialisation.ToBytesSerialiser;

/**
 * A {@code HllSketchSerialiser} serialises a {@link org.apache.datasketches.hll.HllSketch} using its
 * {@code toCompactByteArray()} method.
 */
public class HllSketchSerialiser implements ToBytesSerialiser {
    private static final long serialVersionUID = 5903372368174309494L;

    @Override
    public boolean canHandle(final Class clazz) {
        return HllSketch.class.equals(clazz);
    }

    @Override
    public byte[] serialise(final HllSketch sketch) throws SerialisationException {
        return sketch.toCompactByteArray();
    }

    @Override
    public HllSketch deserialise(final byte[] bytes) throws SerialisationException {
        return HllSketch.heapify(bytes);
    }

    @Override
    public HllSketch deserialiseEmpty() throws SerialisationException {
        return null;
    }

    @Override
    public boolean preservesObjectOrdering() {
        return false;
    }

    @Override
    public boolean isConsistent() {
        return false;
    }

    @Override
    public boolean equals(final Object obj) {
        return this == obj || obj != null && this.getClass() == obj.getClass();
    }

    @Override
    public int hashCode() {
        return HllSketchSerialiser.class.getName().hashCode();
    }
}