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     * {@link TrieUtils} should not normally be instantiated.
030     */
031    private TrieUtils() {}
032
033    /**
034     * Returns an unmodifiable instance of a {@link Trie}
035     *
036     * @param <K>  the key type
037     * @param <V>  the value type
038     * @param trie  the trie to make unmodifiable, must not be null
039     * @return an unmodifiable trie backed by the given trie
040     * @throws NullPointerException if trie is null
041     *
042     * @see java.util.Collections#unmodifiableMap(java.util.Map)
043     */
044    public static <K, V> Trie<K, V> unmodifiableTrie(final Trie<K, ? extends V> trie) {
045        return UnmodifiableTrie.unmodifiableTrie(trie);
046    }
047
048}