001/*
002 * Copyright 2012-2015 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
019/**
020 * Strategy used to handle launch failures.
021 *
022 * @author Phillip Webb
023 * @since 1.3.0
024 */
025public interface FailureHandler {
026
027        /**
028         * {@link FailureHandler} that always aborts.
029         */
030        FailureHandler NONE = new FailureHandler() {
031
032                @Override
033                public Outcome handle(Throwable failure) {
034                        return Outcome.ABORT;
035                }
036
037        };
038
039        /**
040         * Handle a run failure. Implementations may block, for example to wait until specific
041         * files are updated.
042         * @param failure the exception
043         * @return the outcome
044         */
045        Outcome handle(Throwable failure);
046
047        /**
048         * Various outcomes for the handler.
049         */
050        enum Outcome {
051
052                /**
053                 * Abort the relaunch.
054                 */
055                ABORT,
056
057                /**
058                 * Try again to relaunch the application.
059                 */
060                RETRY
061
062        }
063
064}