    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.collections4;
    018
    019import org.apache.commons.collections4.trie.UnmodifiableTrie;
    020
    021/**
    022 * A collection of {@link Trie} utilities.
    023 *
    024 * @since 4.0
    025 */
    026public class TrieUtils {
    027
    028    /**
    029     * Returns an unmodifiable instance of a {@link Trie}
    030     *
    031     * @param <K>  the key type
    032     * @param <V>  the value type
    033     * @param trie  the trie to make unmodifiable, must not be null
    034     * @return an unmodifiable trie backed by the given trie
    035     * @throws NullPointerException if trie is null
    036     * @see java.util.Collections#unmodifiableMap(java.util.Map)
    037     */
    038    public static <K, V> Trie<K, V> unmodifiableTrie(final Trie<K, ? extends V> trie) {
    039        return UnmodifiableTrie.unmodifiableTrie(trie);
    040    }
    041
    042    /**
    043     * Don't allow instances.
    044     */
    045    private TrieUtils() {
    046        // empty
    047    }
    048
    049}