001/*
002 * Java Genetic Algorithm Library (jenetics-7.2.0).
003 * Copyright (c) 2007-2023 Franz Wilhelmstötter
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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 *
017 * Author:
018 *    Franz Wilhelmstötter (franz.wilhelmstoetter@gmail.com)
019 */
020package io.jenetics.ext.internal.parser;
021
022import java.util.Objects;
023import java.util.stream.Stream;
024
025/**
026 * Interface for all tokenizers.
027 *
028 * @param <T> the token value type
029 *
030 * @author <a href="mailto:franz.wilhelmstoetter@gmail.com">Franz Wilhelmstötter</a>
031 * @since 7.1
032 * @version 7.1
033 */
034@FunctionalInterface
035public interface Tokenizer<T> {
036
037        /**
038         * Return the next available <em>token</em>, or {@code null} if no further
039         * tokens are available.
040         *
041         * @return the next available token
042         */
043        T next();
044
045        /**
046         * Return a stream of tokens, generated by {@code this} tokenizer. The
047         * returned stream terminates, when the {@code null}-token is encountered.
048         *
049         * @return a new tokens stream of {@code this} tokenizer
050         */
051        default Stream<T> tokens() {
052                return Stream.generate(this::next).takeWhile(Objects::nonNull);
053        }
054
055}