001/*
002 * Copyright 2012-2017 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.boot.devtools.restart;
018
019import java.net.URL;
020
021/**
022 * Strategy interface used to initialize a {@link Restarter}.
023 *
024 * @author Phillip Webb
025 * @since 1.3.0
026 * @see DefaultRestartInitializer
027 */
028@FunctionalInterface
029public interface RestartInitializer {
030
031        /**
032         * {@link RestartInitializer} that doesn't return any URLs.
033         */
034        RestartInitializer NONE = (thread) -> null;
035
036        /**
037         * Return the initial set of URLs for the {@link Restarter} or {@code null} if no
038         * initial restart is required.
039         * @param thread the source thread
040         * @return initial URLs or {@code null}
041         */
042        URL[] getInitialUrls(Thread thread);
043
044}