UnorderedLocalDescriptor.java

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package org.egothor.stemmer.trie;

import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

/**
 * Local descriptor preserving only unordered {@code getAll()} membership.
 */
/* default */ final class UnorderedLocalDescriptor {

    /**
     * Unordered distinct values.
     */
    private final Set<Object> distinctValues;

    /**
     * Creates a descriptor.
     *
     * @param distinctValues distinct values
     */
    private UnorderedLocalDescriptor(final Set<Object> distinctValues) {
        this.distinctValues = distinctValues;
    }

    /**
     * Creates a descriptor from an ordered value array.
     *
     * @param orderedValues ordered values
     * @return descriptor
     */
    @SuppressWarnings("PMD.UseVarargs")
    /* default */ static UnorderedLocalDescriptor of(final Object[] orderedValues) {
        final Set<Object> distinct = new HashSet<>();
        distinct.addAll(Arrays.asList(orderedValues));
        return new UnorderedLocalDescriptor(Collections.unmodifiableSet(distinct));
    }

    @Override
    public int hashCode() {
        return this.distinctValues.hashCode();
    }

    @Override
    public boolean equals(final Object other) {
        if (this == other) {
            return true;
        }
        if (!(other instanceof UnorderedLocalDescriptor)) {
            return false;
        }
        final UnorderedLocalDescriptor that = (UnorderedLocalDescriptor) other;
        return this.distinctValues.equals(that.distinctValues);
    }
}