Java example source code file (LocalWorkRetriever.java)

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Java - Java tags/keywords

collection, concurrenthashmap, entrylistener, file, imap, job, localworkretriever, map, override, string, threading, threads, util, work_retriever

The LocalWorkRetriever.java Java example source code

/*
 *
 *  * Copyright 2015 Skymind,Inc.
 *  *
 *  *    Licensed 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.deeplearning4j.scaleout.statetracker.workretriever;


import com.hazelcast.core.*;
import org.deeplearning4j.scaleout.job.Job;
import org.deeplearning4j.scaleout.api.statetracker.WorkRetriever;
import org.deeplearning4j.util.SerializationUtils;

import java.io.File;
import java.util.Collection;
import java.util.HashSet;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
 * Local worker retriever
 * @author Adam Gibson
 */
public class LocalWorkRetriever implements WorkRetriever {

    private Map<String,String> workerData = new ConcurrentHashMap<>();
    private IMap<String,Job> distributedData;
    public final static String WORK_RETRIEVER = "workretriever";
    public LocalWorkRetriever() {}

    public LocalWorkRetriever(HazelcastInstance instance) {
        distributedData = instance.getMap(WORK_RETRIEVER);
        distributedData.addEntryListener(new EntryListener<String, Job>() {
            @Override
            public void entryAdded(EntryEvent<String, Job> event) {
                String worker = event.getKey();
                File f = new File(worker + "-work");
                SerializationUtils.saveObject(event.getValue(), f);
                workerData.put(worker,f.getAbsolutePath());
                //only needed for the save event
                distributedData.remove(worker);

            }

            @Override
            public void entryRemoved(EntryEvent<String, Job> event) {

            }

            @Override
            public void entryUpdated(EntryEvent<String, Job> event) {

            }

            @Override
            public void entryEvicted(EntryEvent<String, Job> event) {

            }

            @Override
            public void mapEvicted(MapEvent mapEvent) {

            }

            @Override
            public void mapCleared(MapEvent mapEvent) {

            }
        },true);
    }


    /**
     * Clears the worker
     *
     * @param worker the worker to clear
     */
    @Override
    public void clear(String worker) {
        workerData.remove(worker);
    }

    /**
     * The collection of workers that are saved
     *
     * @return the collection of workers that have data saved
     */
    @Override
    public Collection<String> workers() {
        return new HashSet<>(workerData.keySet());
    }

    /**
     * Loads the data applyTransformToDestination
     *
     * @param worker the worker to load for
     * @return the data for the given worker or null
     */
    @Override
    public Job load(String worker) {
        File f = workerData.get(worker) != null ? new File(workerData.get(worker)) : null;
        if(f == null || !f.exists())
            return null;
        Job d = SerializationUtils.readObject(f);
        workerData.remove(f);
        f.delete();
        return d;
    }

    /**
     * Saves the data  for a given worker
     *
     * @param worker the worker to save data for
     * @param data   the data to save
     */
    @Override
    public void save(String worker, Job data){
        if(distributedData != null)
            distributedData.put(worker,data);

        else {
            File f = new File(worker + "-work");
            SerializationUtils.saveObject(data,f);
            workerData.put(worker,f.getAbsolutePath());
        }



    }
}