Java example source code file (LabelsSource.java)

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Java - Java tags/keywords

arraylist, atomiclong, labelssource, list, serializable, setter, string, util

The LabelsSource.java Java example source code

package org.deeplearning4j.text.documentiterator;

import lombok.NonNull;
import lombok.Setter;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;

/**
 * This class is used to manage labels/documents syncronization over iterators
 *
 * @author raver119@gmail.com
 */
public class LabelsSource implements Serializable {
    private AtomicLong counter = new AtomicLong(0);
    @Setter private String template;
    private boolean useFormatter = false;
    private List<String> labels;
    private long maxCount = 0;

    public LabelsSource() {

    }

    /**
     * Build LabelsSource using string template.
     * Template can be raw string, in this case document counter will be appended to resulting label.
     * I.e. "SENT_" template will produce labels SENT_0, SENT_1, SENT_2 etc.
     *
     * You can also use %d formatter tag, which will be replaced with counter.
     * I.e. "SENT_%i_FLOW_1" will produce labels "SENT_0_FLOW_1", "SENT_1_FLOW_1", "SENT_2_FLOW_1" etc
     *
     * @param template
     */
    public LabelsSource(@NonNull String template) {
        this.template = template;
        if (this.template.contains("%d")) useFormatter = true;
    }

    public int indexOf(String label) {
        return labels.indexOf(label);
    }

    public int size() {
        return labels.size();
    }

    /**
     * Build LabelsSource using externally defined list of string labels.
     * Please note, in this case you have to make sure, the number of documents and number of labels match.
     *
     * @param labels
     */
    public LabelsSource(@NonNull List<String> labels) {
        this.labels = new ArrayList<>(labels);
    }

    /**
     * Returns next label.
     *
     * @return next label, generated or predefined one
     */
    public synchronized String nextLabel() {
        if (labels != null) {
            return labels.get(((Long) counter.getAndIncrement()).intValue());
        } else {
            maxCount = counter.getAndIncrement();
            return formatLabel(maxCount);
        }
    }

    private String formatLabel(long value) {
        if (useFormatter) return String.format(template, value);
        else return template + value;
    }

    /**
     * This method returns the list of labels used by this generator instance.
     * If external list os labels was used as source, whole list will be returned.
     *
     * @return list of labels
     */
    public List<String> getLabels() {
        if (labels != null && !labels.isEmpty()) return labels;
            else {
                List<String> result = new ArrayList<>();
                for (long x = 0; x< counter.get(); x++) result.add(formatLabel(x));
                return result;
        }
    }

    /**
     * This method is intended for storing labels retrieved from external sources.
     *
     * @param label
     */
    public synchronized void storeLabel(String label) {
        if (labels == null) labels = new ArrayList<String>();

        if (!labels.contains(label)) labels.add(label);
    }

    /**
     * This method should be called from Iterator's reset() method, to keep labels in sync with iterator
     */
    public void reset() {
        this.counter.set(0);
    }

    /**
     * This method returns number of labels used up to the method's call
     *
     * @return
     */
    public int getNumberOfLabelsUsed() {
        if (labels != null && !labels.isEmpty()) return labels.size();
            else return ((Long) (maxCount + 1)).intValue();
    }
}