ScopeInstance.java

/*
 * 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 gobblin.broker.iface;

/**
 * A specific scope for a {@link ScopeType}. For example, each task in a process could be a different scope.
 *
 * <p>
 *   Note: {@link ScopeInstance}s will be rendered using {@link #toString()}, and will be compared using
 *   {@link #equals(Object)}. It is important to implement appropriate {@link #equals(Object)} and {@link #hashCode()}
 *   for correct functionality of {@link SharedResourcesBroker}. For example, if a scope for the same task is created
 *   in two different locations, they should still be equal under {@link #equals(Object)}.
 * </p>
 *
 * @param <S> the {@link ScopeType} tree that this scope belongs to.
 */
public interface ScopeInstance<S extends ScopeType<S>> {
  /**
   * @return type of {@link ScopeType}.
   */
  S getType();

  /**
   * @return a String identifying this scope.
   */
  String getScopeId();
}