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.context.properties;
018
019import java.lang.annotation.Documented;
020import java.lang.annotation.ElementType;
021import java.lang.annotation.Retention;
022import java.lang.annotation.RetentionPolicy;
023import java.lang.annotation.Target;
024
025/**
026 * Indicates that a field in a {@link ConfigurationProperties} object should be treated as
027 * if it were a nested type. This annotation has no bearing on the actual binding
028 * processes, but it is used by the {@code spring-boot-configuration-processor} as a hint
029 * that a field is not bound as a single value. When this is specified, a nested group is
030 * created for the field and its type is harvested.
031 * <p>
032 * This has no effect on collections and maps as these types are automatically identified.
033 *
034 * @author Stephane Nicoll
035 * @author Phillip Webb
036 * @since 1.2.0
037 */
038@Target(ElementType.FIELD)
039@Retention(RetentionPolicy.RUNTIME)
040@Documented
041public @interface NestedConfigurationProperty {
042
043}