CompiledNode.java

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package org.egothor.stemmer.trie;

import java.util.Arrays;

/**
 * Immutable compiled trie node optimized for read access.
 *
 * <p>
 * The returned arrays are the internal backing storage of the compiled node.
 * They are exposed for efficient access by closely related trie infrastructure
 * and therefore must never be modified by callers.
 *
 * @param <V>           value type
 * @param edgeLabels    internal edge label array
 * @param children      internal child array
 * @param orderedValues internal ordered values array
 * @param orderedCounts internal ordered counts array
 */
public record CompiledNode<V>(char[] edgeLabels, CompiledNode<V>[] children, V[] orderedValues, int... orderedCounts) {

    /**
     * Finds a child for the supplied edge character.
     *
     * @param edge edge character
     * @return child node, or {@code null} if absent
     */
    public CompiledNode<V> findChild(final char edge) {
        final int index = Arrays.binarySearch(this.edgeLabels, edge);
        if (index < 0) {
            return null;
        }
        return this.children[index];
    }
}