FrequencyTrieBuilders.java

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package org.egothor.stemmer;

import java.util.Objects;

import java.util.function.IntFunction;

import java.util.logging.Level;

import java.util.logging.Logger;

import org.egothor.stemmer.trie.CompiledNode;

/**

 * Factory utilities related to {@link FrequencyTrie.Builder}.

 *

 * <p>

 * This helper reconstructs writable builders from compiled read-only tries. The

 * reconstruction preserves the semantics and local counts of the compiled trie

 * as currently stored, which makes it suitable for subsequent modifications

 * followed by recompilation.

 *

 * <p>

 * Reconstruction operates on the compiled form. Therefore, if the compiled trie

 * was produced using a reduction mode that merged semantically equivalent

 * subtrees, the recreated builder reflects that reduced compiled state rather

 * than the exact original unreduced insertion history.

 */

public final class FrequencyTrieBuilders {

    /**

     * Logger of this class.

     */

    /**

     * Utility class.

     */

    }

    /**

     * Reconstructs a new writable builder from a compiled read-only trie.

     *

     * <p>

     * The returned builder contains the same key-local value counts as the supplied

     * compiled trie. Callers may continue modifying the returned builder and then

     * compile a new {@link FrequencyTrie} instance.

     *

     * @param source            source compiled trie

     * @param arrayFactory      array factory for the reconstructed builder

     * @param reductionSettings reduction settings to associate with the new builder

     * @param <V>               value type

     * @return reconstructed writable builder

     * @throws NullPointerException if any argument is {@code null}

     */

    public static <V> FrequencyTrie.Builder<V> copyOf(final FrequencyTrie<V> source,

            final IntFunction<V[]> arrayFactory, final ReductionSettings reductionSettings) {

    }

    /**

     * Reconstructs a new writable builder from a compiled read-only trie using

     * default settings for the supplied reduction mode.

     *

     * @param source        source compiled trie

     * @param arrayFactory  array factory for the reconstructed builder

     * @param reductionMode reduction mode to associate with the new builder

     * @param <V>           value type

     * @return reconstructed writable builder

     * @throws NullPointerException if any argument is {@code null}

     */

    public static <V> FrequencyTrie.Builder<V> copyOf(final FrequencyTrie<V> source,

            final IntFunction<V[]> arrayFactory, final ReductionMode reductionMode) {

    }

    /**

     * Copies one compiled node and all reachable descendants into the target

     * builder.

     *

     * @param node       current compiled node

     * @param keyBuilder current key builder

     * @param builder    target mutable builder

     * @param <V>        value type

     */

    private static <V> void copyNode(final CompiledNode<V> node, final StringBuilder keyBuilder,

            final FrequencyTrie.Builder<V> builder) {

        }

        }

}

Mutations