001/*
002 * Copyright 2002-2017 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 *      https://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.context;
018
019import org.springframework.lang.Nullable;
020
021/**
022 * Interface for objects that are suitable for message resolution in a
023 * {@link MessageSource}.
024 *
025 * <p>Spring's own validation error classes implement this interface.
026 *
027 * @author Juergen Hoeller
028 * @see MessageSource#getMessage(MessageSourceResolvable, java.util.Locale)
029 * @see org.springframework.validation.ObjectError
030 * @see org.springframework.validation.FieldError
031 */
032@FunctionalInterface
033public interface MessageSourceResolvable {
034
035        /**
036         * Return the codes to be used to resolve this message, in the order that
037         * they should get tried. The last code will therefore be the default one.
038         * @return a String array of codes which are associated with this message
039         */
040        @Nullable
041        String[] getCodes();
042
043        /**
044         * Return the array of arguments to be used to resolve this message.
045         * <p>The default implementation simply returns {@code null}.
046         * @return an array of objects to be used as parameters to replace
047         * placeholders within the message text
048         * @see java.text.MessageFormat
049         */
050        @Nullable
051        default Object[] getArguments() {
052                return null;
053        }
054
055        /**
056         * Return the default message to be used to resolve this message.
057         * <p>The default implementation simply returns {@code null}.
058         * Note that the default message may be identical to the primary
059         * message code ({@link #getCodes()}), which effectively enforces
060         * {@link org.springframework.context.support.AbstractMessageSource#setUseCodeAsDefaultMessage}
061         * for this particular message.
062         * @return the default message, or {@code null} if no default
063         */
064        @Nullable
065        default String getDefaultMessage() {
066                return null;
067        }
068
069}