DiacriticProcessingMode.java

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package org.egothor.stemmer;

/**
 * Defines how dictionary loading and trie traversal should treat diacritics.
 *
 * <p>
 * The selected mode is applied independently from other normalization modes
 * (for example {@link CaseProcessingMode}). This means case normalization and
 * diacritic normalization can be combined freely and each keeps its own
 * semantics.
 * </p>
 */
public enum DiacriticProcessingMode {

    /**
     * Preserves dictionary entries and lookup keys exactly as provided.
     */
    AS_IS,

    /**
     * Removes diacritics from dictionary entries before trie construction and
     * removes diacritics from lookup keys before traversal.
     */
    REMOVE,

    /**
     * Planned dual-path mode where lookup may continue along both the original
     * diacritic edge and a normalized non-diacritic alternative.
     *
     * <p>
     * This mode is currently not supported and using it triggers
     * {@link UnsupportedOperationException}.
     * </p>
     */
    AS_IS_AND_STRIPPED_FALLBACK
}