org.apache.druid.segment.realtime.plumber.MessageTimeRejectionPolicyFactory.java Source code

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Here is the source code for org.apache.druid.segment.realtime.plumber.MessageTimeRejectionPolicyFactory.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.druid.segment.realtime.plumber;

import org.apache.druid.java.util.common.DateTimes;
import org.apache.druid.java.util.common.JodaUtils;
import org.apache.druid.java.util.common.StringUtils;
import org.joda.time.DateTime;
import org.joda.time.Period;

import java.util.concurrent.atomic.AtomicLongFieldUpdater;

public class MessageTimeRejectionPolicyFactory implements RejectionPolicyFactory {
    @Override
    public RejectionPolicy create(final Period windowPeriod) {
        final long windowMillis = windowPeriod.toStandardDuration().getMillis();
        return new MessageTimeRejectionPolicy(windowMillis, windowPeriod);
    }

    private static class MessageTimeRejectionPolicy implements RejectionPolicy {
        private static final AtomicLongFieldUpdater<MessageTimeRejectionPolicy> maxTimestampUpdater = AtomicLongFieldUpdater
                .newUpdater(MessageTimeRejectionPolicy.class, "maxTimestamp");
        private final long windowMillis;
        private final Period windowPeriod;
        private volatile long maxTimestamp;

        public MessageTimeRejectionPolicy(long windowMillis, Period windowPeriod) {
            this.windowMillis = windowMillis;
            this.windowPeriod = windowPeriod;
            this.maxTimestamp = JodaUtils.MIN_INSTANT;
        }

        @Override
        public DateTime getCurrMaxTime() {
            return DateTimes.utc(maxTimestamp);
        }

        @Override
        public boolean accept(long timestamp) {
            long maxTimestamp = this.maxTimestamp;
            if (timestamp > maxTimestamp) {
                maxTimestamp = tryUpdateMaxTimestamp(timestamp);
            }

            return timestamp >= (maxTimestamp - windowMillis);
        }

        private long tryUpdateMaxTimestamp(long timestamp) {
            long currentMaxTimestamp;
            do {
                currentMaxTimestamp = maxTimestamp;
                if (timestamp <= currentMaxTimestamp) {
                    return currentMaxTimestamp;
                }
            } while (!maxTimestampUpdater.compareAndSet(this, currentMaxTimestamp, timestamp));
            return timestamp;
        }

        @Override
        public String toString() {
            return StringUtils.format("messageTime-%s", windowPeriod);
        }
    }
}