com.metamx.druid.BaseQuery.java Source code

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Here is the source code for com.metamx.druid.BaseQuery.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;

import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.base.Preconditions;
import com.google.common.collect.Maps;
import com.metamx.common.guava.Sequence;
import com.metamx.druid.query.QueryRunner;
import com.metamx.druid.query.segment.QuerySegmentSpec;
import com.metamx.druid.query.segment.QuerySegmentWalker;

import org.joda.time.Duration;
import org.joda.time.Interval;

import java.util.List;
import java.util.Map;

/**
 */
public abstract class BaseQuery<T> implements Query<T> {
    private final String dataSource;
    private final Map<String, String> context;
    private final QuerySegmentSpec querySegmentSpec;

    private volatile Duration duration;

    public BaseQuery(String dataSource, QuerySegmentSpec querySegmentSpec, Map<String, String> context) {
        Preconditions.checkNotNull(dataSource, "dataSource can't be null");
        Preconditions.checkNotNull(querySegmentSpec, "querySegmentSpec can't be null");

        this.dataSource = dataSource.toLowerCase();
        this.context = context;
        this.querySegmentSpec = querySegmentSpec;

    }

    @JsonProperty
    @Override
    public String getDataSource() {
        return dataSource;
    }

    @JsonProperty("intervals")
    public QuerySegmentSpec getQuerySegmentSpec() {
        return querySegmentSpec;
    }

    @Override
    public Sequence<T> run(QuerySegmentWalker walker) {
        return run(querySegmentSpec.lookup(this, walker));
    }

    public Sequence<T> run(QueryRunner<T> runner) {
        return runner.run(this);
    }

    @Override
    public List<Interval> getIntervals() {
        return querySegmentSpec.getIntervals();
    }

    @Override
    public Duration getDuration() {
        if (duration == null) {
            Duration totalDuration = new Duration(0);
            for (Interval interval : querySegmentSpec.getIntervals()) {
                if (interval != null) {
                    totalDuration = totalDuration.plus(interval.toDuration());
                }
            }
            duration = totalDuration;
        }

        return duration;
    }

    @JsonProperty
    public Map<String, String> getContext() {
        return context;
    }

    @Override
    public String getContextValue(String key) {
        return context == null ? null : context.get(key);
    }

    @Override
    public String getContextValue(String key, String defaultValue) {
        String retVal = getContextValue(key);
        return retVal == null ? defaultValue : retVal;
    }

    protected Map<String, String> computeOverridenContext(Map<String, String> overrides) {
        Map<String, String> overridden = Maps.newTreeMap();
        final Map<String, String> context = getContext();
        if (context != null) {
            overridden.putAll(context);
        }
        overridden.putAll(overrides);

        return overridden;
    }
}