Java tutorial
/** * This file is part of Graylog. * * Graylog 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 3 of the License, or * (at your option) any later version. * * Graylog 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 Graylog. If not, see <http://www.gnu.org/licenses/>. */ package org.graylog2.indexer.results; import com.google.common.collect.ImmutableMap; import com.google.common.collect.Maps; import org.elasticsearch.common.bytes.BytesReference; import org.elasticsearch.common.unit.TimeValue; import org.elasticsearch.search.aggregations.bucket.histogram.Histogram; import org.elasticsearch.search.aggregations.metrics.cardinality.Cardinality; import org.elasticsearch.search.aggregations.metrics.stats.Stats; import org.graylog2.indexer.searches.Searches; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.joda.time.MutableDateTime; import java.util.Collections; import java.util.Map; public class FieldHistogramResult extends HistogramResult { private static final Map<String, Number> EMPTY_RESULT = ImmutableMap.<String, Number>builder().put("count", 0) .put("min", 0).put("max", 0).put("total", 0).put("total_count", 0).put("mean", 0).build(); private final Histogram result; private final Searches.DateHistogramInterval interval; public FieldHistogramResult(Histogram result, String originalQuery, BytesReference builtQuery, Searches.DateHistogramInterval interval, TimeValue took) { super(originalQuery, builtQuery, took); this.result = result; this.interval = interval; } @Override public Searches.DateHistogramInterval getInterval() { return interval; } @Override public Map<Long, Map<String, Number>> getResults() { if (result.getBuckets().isEmpty()) { return Collections.emptyMap(); } final Map<Long, Map<String, Number>> results = Maps.newTreeMap(); for (Histogram.Bucket b : result.getBuckets()) { final ImmutableMap.Builder<String, Number> resultMap = ImmutableMap.builder(); resultMap.put("total_count", b.getDocCount()); final Stats stats = b.getAggregations().get(Searches.AGG_STATS); resultMap.put("count", stats.getCount()); resultMap.put("min", stats.getMin()); resultMap.put("max", stats.getMax()); resultMap.put("total", stats.getSum()); resultMap.put("mean", stats.getAvg()); // cardinality is only calculated if it was explicitly requested, so this might be null final Cardinality cardinality = b.getAggregations().get(Searches.AGG_CARDINALITY); resultMap.put("cardinality", cardinality == null ? 0 : cardinality.getValue()); final DateTime keyAsDate = (DateTime) b.getKey(); final long timestamp = keyAsDate.getMillis() / 1000L; results.put(timestamp, resultMap.build()); } final long minTimestamp = Collections.min(results.keySet()); final long maxTimestamp = Collections.max(results.keySet()); final MutableDateTime currentTime = new MutableDateTime(minTimestamp, DateTimeZone.UTC); while (currentTime.getMillis() < maxTimestamp) { final Map<String, Number> entry = results.get(currentTime.getMillis()); // advance timestamp by the interval's seconds value currentTime.add(interval.getPeriod()); if (entry == null) { // synthesize a 0 value for this timestamp results.put(currentTime.getMillis(), EMPTY_RESULT); } } return results; } }