/*
 * Copyright 2020 The Apache Software Foundation.
 *
 * Licensed 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.bookkeeper.client.api;

import java.io.IOException;

/**
 * Iterator for ledgers.
 */
public interface LedgersIterator {

    /**
     * Return true if there is at least one ledger to visit.
     *
     * @return true if there is at least one ledger to visit.
     * @throws IOException thrown when there is a problem accessing the ledger metadata store.
     */
    boolean hasNext() throws IOException;

    /**
     * Return next ledger id.
     *
     * @return next ledger id.
     * @throws IOException thrown when there is a problem accessing the ledger metadata store.
     */
    long next() throws IOException;

}
