com.metamx.druid.merger.common.task.DefaultMergeTask.java Source code

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Here is the source code for com.metamx.druid.merger.common.task.DefaultMergeTask.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 com.metamx.druid.merger.common.task;

import com.google.common.base.Function;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import com.metamx.druid.aggregation.AggregatorFactory;
import com.metamx.druid.client.DataSegment;
import com.metamx.druid.index.QueryableIndex;
import com.metamx.druid.index.v1.IndexIO;
import com.metamx.druid.index.v1.IndexMerger;
import org.codehaus.jackson.annotate.JsonCreator;
import org.codehaus.jackson.annotate.JsonProperty;

import javax.annotation.Nullable;
import java.io.File;
import java.util.List;
import java.util.Map;

/**
 */
public class DefaultMergeTask extends MergeTask {
    private final List<AggregatorFactory> aggregators;

    @JsonCreator
    public DefaultMergeTask(@JsonProperty("dataSource") String dataSource,
            @JsonProperty("segments") List<DataSegment> segments,
            @JsonProperty("aggregations") List<AggregatorFactory> aggregators) {
        super(dataSource, segments);
        this.aggregators = aggregators;
    }

    @Override
    public File merge(final Map<DataSegment, File> segments, final File outDir) throws Exception {
        return IndexMerger.mergeQueryableIndex(
                Lists.transform(ImmutableList.copyOf(segments.values()), new Function<File, QueryableIndex>() {
                    @Override
                    public QueryableIndex apply(@Nullable File input) {
                        try {
                            return IndexIO.loadIndex(input);
                        } catch (Exception e) {
                            throw Throwables.propagate(e);
                        }
                    }
                }), aggregators.toArray(new AggregatorFactory[aggregators.size()]), outDir);
    }

    @Override
    public Type getType() {
        return Task.Type.MERGE;
    }
}