Java tutorial
/* * 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.indexing.common.task; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.google.common.base.Function; import com.google.common.base.Preconditions; import com.google.common.base.Predicate; import com.google.common.collect.Lists; import com.google.common.collect.Ordering; import com.metamx.druid.TimelineObjectHolder; import com.metamx.druid.VersionedIntervalTimeline; import com.metamx.druid.client.DataSegment; import com.metamx.druid.index.v1.IndexIO; import com.metamx.druid.index.v1.IndexMerger; import com.metamx.druid.index.v1.IndexableAdapter; import com.metamx.druid.index.v1.QueryableIndexIndexableAdapter; import com.metamx.druid.index.v1.Rowboat; import com.metamx.druid.index.v1.RowboatFilteringIndexAdapter; import org.joda.time.Interval; import javax.annotation.Nullable; import java.io.File; import java.util.List; import java.util.Map; /** */ public class AppendTask extends MergeTaskBase { @JsonCreator public AppendTask(@JsonProperty("id") String id, @JsonProperty("dataSource") String dataSource, @JsonProperty("segments") List<DataSegment> segments) { super(id, dataSource, segments); } @Override public File merge(final Map<DataSegment, File> segments, final File outDir) throws Exception { VersionedIntervalTimeline<String, DataSegment> timeline = new VersionedIntervalTimeline<String, DataSegment>( Ordering.<String>natural().nullsFirst()); for (DataSegment segment : segments.keySet()) { timeline.add(segment.getInterval(), segment.getVersion(), segment.getShardSpec().createChunk(segment)); } final List<SegmentToMergeHolder> segmentsToMerge = Lists.transform( timeline.lookup(new Interval("1000-01-01/3000-01-01")), new Function<TimelineObjectHolder<String, DataSegment>, SegmentToMergeHolder>() { @Override public SegmentToMergeHolder apply(TimelineObjectHolder<String, DataSegment> input) { final DataSegment segment = input.getObject().getChunk(0).getObject(); final File file = Preconditions.checkNotNull(segments.get(segment), "File for segment %s", segment.getIdentifier()); return new SegmentToMergeHolder(segment, input.getInterval(), file); } }); List<IndexableAdapter> adapters = Lists.newArrayList(); for (final SegmentToMergeHolder holder : segmentsToMerge) { adapters.add(new RowboatFilteringIndexAdapter( new QueryableIndexIndexableAdapter(IndexIO.loadIndex(holder.getFile())), new Predicate<Rowboat>() { @Override public boolean apply(@Nullable Rowboat input) { return holder.getInterval().contains(input.getTimestamp()); } })); } return IndexMerger.append(adapters, outDir); } @Override public String getType() { return "append"; } private class SegmentToMergeHolder { private final DataSegment segment; private final Interval interval; private final File file; private SegmentToMergeHolder(DataSegment segment, Interval interval, File file) { this.segment = segment; this.interval = interval; this.file = file; } public DataSegment getSegment() { return segment; } public Interval getInterval() { return interval; } public File getFile() { return file; } } }