io.druid.query.aggregation.HyperloglogDruidModule.java Source code

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Here is the source code for io.druid.query.aggregation.HyperloglogDruidModule.java

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/*
 * Druid - a distributed column store.
 * Copyright (C) 2012  Metamarkets Group Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package io.druid.query.aggregation;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.Module;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.jsontype.NamedType;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.google.common.collect.ImmutableList;
import com.google.inject.Binder;
import gnu.trove.map.hash.TIntByteHashMap;
import io.druid.initialization.DruidModule;
import io.druid.segment.serde.ComplexMetrics;
import org.apache.commons.codec.binary.Base64;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.List;

/**
 */
public class HyperloglogDruidModule implements DruidModule {
    @Override
    public List<? extends Module> getJacksonModules() {
        return ImmutableList.of(new HyperloglogJacksonSerdeModule()
                .registerSubtypes(new NamedType(HyperloglogAggregatorFactory.class, "hyperloglog")));
    }

    @Override
    public void configure(Binder binder) {
        if (ComplexMetrics.getSerdeForType("hyperloglog") == null) {
            ComplexMetrics.registerSerde("hyperloglog", new HyperloglogComplexMetricSerde());
        }
    }

    public static class HyperloglogJacksonSerdeModule extends SimpleModule {
        public HyperloglogJacksonSerdeModule() {
            super("Hyperloglog deserializers");

            addDeserializer(TIntByteHashMap.class, new JsonDeserializer<TIntByteHashMap>() {
                @Override
                public TIntByteHashMap deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException {
                    byte[] ibmapByte = Base64.decodeBase64(jp.getText());

                    ByteBuffer buffer = ByteBuffer.wrap(ibmapByte);
                    int keylength = buffer.getInt();
                    int valuelength = buffer.getInt();
                    if (keylength == 0) {
                        return (new TIntByteHashMap());
                    }
                    int[] keys = new int[keylength];
                    byte[] values = new byte[valuelength];

                    for (int i = 0; i < keylength; i++) {
                        keys[i] = buffer.getInt();
                    }
                    buffer.get(values);

                    return (new TIntByteHashMap(keys, values));
                }
            });

            addSerializer(TIntByteHashMap.class, new JsonSerializer<TIntByteHashMap>() {
                @Override
                public void serialize(TIntByteHashMap ibmap, JsonGenerator jsonGenerator,
                        SerializerProvider serializerProvider) throws IOException, JsonProcessingException {
                    int[] indexesResult = ibmap.keys();
                    byte[] valueResult = ibmap.values();
                    ByteBuffer buffer = ByteBuffer.allocate(4 * indexesResult.length + valueResult.length + 8);
                    byte[] result = new byte[4 * indexesResult.length + valueResult.length + 8];
                    buffer.putInt((int) indexesResult.length);
                    buffer.putInt((int) valueResult.length);
                    for (int i = 0; i < indexesResult.length; i++) {
                        buffer.putInt(indexesResult[i]);
                    }

                    buffer.put(valueResult);
                    buffer.flip();
                    buffer.get(result);
                    String str = Base64.encodeBase64String(result);
                    jsonGenerator.writeString(str);
                }
            });

        }
    }
}