/**
 * 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.apex.engine.api.plugin;

import java.util.Collection;

import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;

/**
 * Interface to discover plugins during Apex Master initialization. This should return collection of
 * objects implementing an interface of type T.
 */
@InterfaceStability.Evolving
public interface PluginLocator<T>
{
  /**
   * Discover list of apex plugins.
   *
   * @return list of apex plugins.
   */
  Collection<T> discoverPlugins(Configuration conf);
}