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.camel;
018
019import java.util.List;
020
021/**
022 * Implementations support navigating a graph where you can traverse forward and each next
023 * returns a {@link List} of outputs of type <tt>T</tt> that can contain <tt>0..n</tt> nodes.
024 */
025public interface Navigate<T> {
026
027    /**
028     * Next group of outputs
029     * <p/>
030     * Important only invoke this once, as this method do not carry state, and is not intended to be used in a while loop,
031     * but used by a if statement instead.
032     *
033     * @return next group or <tt>null</tt> if no more outputs
034     */
035    List<T> next();
036
037    /**
038     * Are there more outputs?
039     * <p/>
040     * Important only invoke this once, as this method do not carry state, and is not intended to be used in a while loop,
041     * but used by a if statement instead.
042     *
043     * @return <tt>true</tt> if more outputs
044     */
045    boolean hasNext();
046
047}