org.apache.flume.annotations.InterfaceAudience Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* to you under the Apache License, Version 2.0 (the
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* 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
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*/
package org.apache.flume.annotations;
import java.lang.annotation.Documented;
/**
* Annotation to inform users of a package, class or method's intended audience.
* Currently the audience can be {@link Public}, {@link LimitedPrivate} or
* {@link Private}.
* All public classes must have InterfaceAudience annotation.
*
* - Public classes that are not marked with this annotation must be
* considered by default as {@link Private}.
*
* - External applications must only use classes that are marked
* {@link Public}. Avoid using non public classes as these classes
* could be removed or change in incompatible ways.
*
* - Flume projects must only use classes that are marked
* {@link LimitedPrivate} or {@link Public}
*
* - Methods may have a different annotation that it is more restrictive
* compared to the audience classification of the class. Example: A class
* might be {@link Public}, but a method may be {@link LimitedPrivate}
*
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
public class InterfaceAudience {
/**
* Intended for use by any project or application.
*/
@Documented public @interface Public {};
/**
* Intended only for the project(s) specified in the annotation.
* For example, "Common", "HDFS", "MapReduce", "ZooKeeper", "HBase".
*/
@Documented public @interface LimitedPrivate {
String[] value();
};
/**
* Intended for use only within Flume
*/
@Documented public @interface Private {};
private InterfaceAudience() {} // Audience can't exist on its own
}