/*
 * 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.carbondata.common.annotations;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/**
 * This annotation is ported and modified from Apache Hadoop project.
 *
 * Annotation to inform users of how much to rely on a particular package,
 * class or method not changing over time. Currently the stability can be
 * {@link Stable}, {@link Evolving} or {@link Unstable}. <br>
 *
 * 1. {@link Stable} means compatibility can break only at major release (m.0)
 * 2. {@link Evolving} means compatibility can break at minor release (m.x)
 * 3. {@link Unstable} means compatibility can break at any release
 *
 * <ul><li>All classes that are annotated with {@link InterfaceAudience.User} or
 * {@link InterfaceAudience.Developer} must have InterfaceStability annotation. </li>
 * <li>Classes that are {@link InterfaceAudience.Internal} are to be considered unstable unless
 * a different InterfaceStability annotation states otherwise.</li>
 * <li>Incompatible changes must not be made to classes marked as stable.</li>
 * </ul>
 */
@InterfaceAudience.User
@org.apache.hadoop.classification.InterfaceStability.Evolving
public class InterfaceStability {
  /**
   * Can evolve while retaining compatibility for minor release boundaries.;
   * can break compatibility only at major release (ie. at m.0).
   */
  @Documented
  @Retention(RetentionPolicy.RUNTIME)
  public @interface Stable { }

  /**
   * Evolving, but can break compatibility at minor release (i.e. m.x)
   */
  @Documented
  @Retention(RetentionPolicy.RUNTIME)
  public @interface Evolving { }

  /**
   * No guarantee is provided as to reliability or stability across any
   * level of release granularity.
   */
  @Documented
  @Retention(RetentionPolicy.RUNTIME)
  public @interface Unstable { }
}
