package org.codelibs.fess.suggest.index.contents.document;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Random;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

         * The queue for URLs waiting to be crawled.
         */
        protected Queue<OpenSearchUrlQueue> waitingQueue = new ConcurrentLinkedQueue<>();

        /**
         * The queue for URLs currently being crawled.
         */
        protected Queue<OpenSearchUrlQueue> crawlingQueue = new ConcurrentLinkedQueue<>();
    }

    /**
     * Sets the polling fetch size.
     * @param pollingFetchSize The polling fetch size.

import java.io.OutputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.time.Duration;
import java.util.HashSet;
import java.util.Queue;
import java.util.Set;
import java.util.concurrent.ConcurrentLinkedQueue;

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPClient.NatServerResolverImpl;