org.apache.druid.guice.annotations.PublicApi Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.druid.guice.annotations;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Signifies that the annotated entity is a public API for extension authors. Public APIs may change in breaking ways
* only between major Druid release lines (e.g. 0.10.x -> 0.11.0), but otherwise must remain stable. Public APIs may
* change at any time in non-breaking ways, however, such as by adding new fields, methods, or constructors.
*
* Note that interfaces annotated with {@code PublicApi} but not with {@link ExtensionPoint} are not meant to be
* subclassed in extensions. In this case, the annotation simply signifies that the interface is stable for callers.
* In particular, since it is not meant to be subclassed, new non-default methods may be added to an interface and
* new abstract methods may be added to a class.
*
* If a class or interface is annotated, then all public and protected fields, methods, and constructors that class
* or interface are considered stable in this sense. If a class is not annotated, but an individual field, method, or
* constructor is annotated, then only that particular field, method, or constructor is considered a public API.
*
* Classes, fields, method, and constructors _not_ annotated with {@code @PublicApi} may be modified or removed
* in any Druid release, unless they are annotated with {@link ExtensionPoint} (which implies they are a public API
* as well).
*
* @see ExtensionPoint
*/
@Target({ElementType.TYPE, ElementType.FIELD, ElementType.METHOD, ElementType.CONSTRUCTOR})
@Retention(RetentionPolicy.SOURCE)
public @interface PublicApi
{
}