/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.elasticsearch.index.store.distributor;

import org.apache.lucene.store.Directory;

/**
 * Keeps track of available directories and selects a directory
 * based on some distribution strategy
 */
public interface Distributor {

    /**
     * Returns primary directory (typically first directory in the list)
     */
    Directory primary();

    /**
     * Returns all directories
     */
    Directory[] all();

    /**
     * Selects one of the directories based on distribution strategy
     */
    Directory any();
}
