org.apache.lens.server.stats.store.log.StatisticsLogRollupHandler.java Source code

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Here is the source code for org.apache.lens.server.stats.store.log.StatisticsLogRollupHandler.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.lens.server.stats.store.log;

import java.util.Timer;

import org.apache.lens.server.api.LensConfConstants;
import org.apache.lens.server.api.events.LensEventService;
import org.apache.lens.server.model.LogSegregationContext;

import org.apache.hadoop.conf.Configuration;

import org.eclipse.jetty.util.ConcurrentHashSet;

import lombok.NonNull;

/**
 * Class which handles the rolled log file.
 */
public class StatisticsLogRollupHandler {

    /** The task. */
    private org.apache.lens.server.stats.store.log.StatisticsLogFileScannerTask task;

    /** The timer. */
    private Timer timer;

    /** The rate. */
    private long rate;

    /** The scan set. */
    private final ConcurrentHashSet<String> scanSet = new ConcurrentHashSet<String>();

    private final LogSegregationContext logSegregationContext;

    public StatisticsLogRollupHandler(@NonNull final LogSegregationContext logSegregationContext) {
        this.logSegregationContext = logSegregationContext;
    }

    /**
     * Initalize the handler.
     *
     * @param conf configuration to be used while initialization.
     */
    public void initialize(Configuration conf) {
        task = new StatisticsLogFileScannerTask(this.logSegregationContext);
        timer = new Timer();
        rate = conf.getLong(LensConfConstants.STATS_ROLLUP_SCAN_RATE,
                LensConfConstants.DEFAULT_STATS_ROLLUP_SCAN_RATE);
    }

    /**
     * Start.
     *
     * @param service the service
     */
    public void start(LensEventService service) {
        task.setService(service);
        timer.scheduleAtFixedRate(task, rate, rate);
    }

    /**
     * Stop.
     */
    public void stop() {
        timer.cancel();
    }

    /**
     * Adds the to scan task.
     *
     * @param event the event
     */
    public void addToScanTask(String event) {
        if (!scanSet.contains(event)) {
            scanSet.add(event);
            task.addLogFile(event);
        }
    }

}