GroupOfOccurrences.java

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package br.ufrgs.inf.prosoft.tfcache.metadata;

import br.ufrgs.inf.prosoft.tfcache.Metrics;
import br.ufrgs.inf.prosoft.tfcache.Simulator;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Objects;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Collectors;
import java.util.stream.LongStream;
import java.util.stream.Stream;

/**
 *
 * @author romulo
 */
public class GroupOfOccurrences {

    private static final Logger LOGGER = Logger.getLogger(GroupOfOccurrences.class.getName());

    private final List<Occurrence> occurrences;
    private final String parameters;

    private Metrics bestMetrics;

    public GroupOfOccurrences(String parameters, List<Occurrence> occurrences) {
        this.parameters = parameters;
        this.occurrences = occurrences;
    }

    public String getParameters() {
        return this.parameters;
    }

    public int getOccurrencesSize() {
        return this.occurrences.size();
    }

    public Metrics getBestMetrics() {
        if (this.bestMetrics == null) {
            throw new RuntimeException("hitsPerTimeInCache must be calculated");
        }
        return this.bestMetrics;
    }

    public Long getTtl() {
        return getBestMetrics().getTtl();
    }

    public Long getSavedTime() {
        return getBestMetrics().getSavedTime();
    }

    public BigDecimal getHitsPerTimeInCache() {
        return getBestMetrics().getHitsPerTimeInCache();
    }

    public Stream<Occurrence> occurrences() {
        return this.occurrences.stream();
    }

    public boolean isChangeable() {
        Iterator<Occurrence> iterator = this.occurrences.iterator();
        Occurrence first = iterator.next();
        while (iterator.hasNext()) {
            Occurrence next = iterator.next();
            if (!Objects.deepEquals(first.getReturnValue(), next.getReturnValue())) {
                return true;
            }
        }
        return false;
    }

    public void calculateHitsPerTimeInCache() {
        if (this.bestMetrics != null) {
            LOGGER.log(Level.WARNING, "HitsPerTimeInCache already calculated");
        }
        if (this.occurrences.size() < 2) {
            throw new RuntimeException("Not reusable input");
        }
        this.bestMetrics = new Metrics();

        Collection<Long> ttlsOfInterest = new HashSet<>();
        for (int hits = 1; hits < this.occurrences.size(); hits++) {
            for (int shift = 0; shift < this.occurrences.size() - hits; shift++) {
                long ttl = 0;
                for (int k = shift + 1; k < shift + 1 + hits; k++) {
                    ttl += this.occurrences.get(k).getStartTime() - this.occurrences.get(k - 1).getEndTime();
                }
                if (ttl > 0) {
                    ttlsOfInterest.add(ttl);
                }
            }
        }
        ttlsOfInterest.stream().parallel().forEach(actualTTL -> {
            Simulator.simulate(occurrences(), actualTTL, this.bestMetrics);
        });
    }

}