BasicCrawlController.java Source code

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Here is the source code for BasicCrawlController.java

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/**
 * 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 edu.uci.ics.crawler4j.examples.basic;

import com.sleepycat.je.txn.LockerFactory;

import edu.uci.ics.crawler4j.crawler.CrawlConfig;
import edu.uci.ics.crawler4j.crawler.CrawlController;
import edu.uci.ics.crawler4j.fetcher.PageFetcher;
import edu.uci.ics.crawler4j.robotstxt.RobotstxtConfig;
import edu.uci.ics.crawler4j.robotstxt.RobotstxtServer;

//import org.slf4j.Logger;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * @author Yasser Ganjisaffar [lastname at gmail dot com]
 */
public class BasicCrawlController {
    private static Log logger = LogFactory.getLog(BasicCrawlController.class);

    public static void main(String[] args) throws Exception {
        if (args.length != 2) {
            System.out.println("Needed parameters: ");
            System.out.println("\t rootFolder (it will contain intermediate crawl data)");
            System.out.println("\t numberOfCralwers (number of concurrent threads)");
            logger.info("\t numberOfCralwers (number of concurrent threads)");
            return;
        }

        /*
         * crawlStorageFolder is a folder where intermediate crawl data is
         * stored.
         */
        String crawlStorageFolder = args[0];

        /*
         * numberOfCrawlers shows the number of concurrent threads that should
         * be initiated for crawling.
         */
        int numberOfCrawlers = Integer.parseInt(args[1]);

        CrawlConfig config = new CrawlConfig();

        config.setCrawlStorageFolder(crawlStorageFolder);

        /*
         * Be polite: Make sure that we don't send more than 1 request per
         * second (1000 milliseconds between requests).
         */
        config.setPolitenessDelay(500);

        config.setUserAgentString("UCI WebCrawler 33762324-78325036-74647602");

        /*
         * You can set the maximum crawl depth here. The default value is -1 for
         * unlimited depth
         */
        config.setMaxDepthOfCrawling(-1);

        /*
         * You can set the maximum number of pages to crawl. The default value
         * is -1 for unlimited number of pages
         */
        //    config.setMaxPagesToFetch(10);

        /**
         * Do you want crawler4j to crawl also binary data ?
         * example: the contents of pdf, or the metadata of images etc
         */
        config.setIncludeBinaryContentInCrawling(false);

        /*
         * Do you need to set a proxy? If so, you can use:
         * config.setProxyHost("proxyserver.example.com");
         * config.setProxyPort(8080);
         *
         * If your proxy also needs authentication:
         * config.setProxyUsername(username); config.getProxyPassword(password);
         */

        /*
         * This config parameter can be used to set your crawl to be resumable
         * (meaning that you can resume the crawl from a previously
         * interrupted/crashed crawl). Note: if you enable resuming feature and
         * want to start a fresh crawl, you need to delete the contents of
         * rootFolder manually.
         */
        config.setResumableCrawling(true);

        /*
         * Instantiate the controller for this crawl.
         */
        PageFetcher pageFetcher = new PageFetcher(config);
        RobotstxtConfig robotstxtConfig = new RobotstxtConfig();
        RobotstxtServer robotstxtServer = new RobotstxtServer(robotstxtConfig, pageFetcher);
        CrawlController controller = new CrawlController(config, pageFetcher, robotstxtServer);

        /*
         * For each crawl, you need to add some seed urls. These are the first
         * URLs that are fetched and then the crawler starts following links
         * which are found in these pages
         */
        controller.addSeed("http://www.ics.uci.edu/");

        /*
         * Start the crawl. This is a blocking operation, meaning that your code
         * will reach the line after this only when crawling is finished.
         */
        controller.start(BasicCrawler.class, numberOfCrawlers);
    }
}