handler.java

这是个爬虫和lucece相结合最好了

/* $Id: Handler.java 4902 2007-02-16 00:07:40Z stack-sf $
 *
 * Created October 28th, 2006
 *
 * Copyright (C) 2006 Internet Archive.
 *
 * This file is part of the Heritrix web crawler (crawler.archive.org).
 *
 * Heritrix is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * any later version.
 *
 * Heritrix is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser Public License
 * along with Heritrix; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package org.archive.net.s3;

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;

import org.jets3t.service.S3ServiceException;
import org.jets3t.service.impl.rest.httpclient.RestS3Service;
import org.jets3t.service.model.S3Bucket;
import org.jets3t.service.model.S3Object;
import org.jets3t.service.security.AWSCredentials;

/**
 * A protocol handler for an s3 scheme. Takes URLs of the form:
 * <code>s3://aws.access.key.id:aws.access.key.secret@BUCKET/PATH</code> (Same
 * as in hadoop).
 * 
 * @author stack
 */
public class Handler extends URLStreamHandler {
    protected URLConnection openConnection(URL u)
    throws IOException {
        // This looking for accessKey id and accessKey secret code is based
        // on code from hadoop S3.
        String accessKey = null;
        String secretAccessKey = null;
        String userInfo = u.getUserInfo();
        if (userInfo != null) {
            int index = userInfo.indexOf(':');
            if (index != -1) {
              accessKey = userInfo.substring(0, index);
              secretAccessKey = userInfo.substring(index + 1);
            } else {
              accessKey = userInfo;
            }
        }
        if (accessKey == null) {
          accessKey = System.getProperty("aws.access.key.id");
        }
        if (secretAccessKey == null) {
          secretAccessKey = System.getProperty("aws.access.key.secret");
        }
        if (accessKey == null && secretAccessKey == null) {
          throw new IllegalArgumentException("AWS " +
                "Access Key ID and Secret Access Key " +
                "must be specified as the username " +
                "or password (respectively) of a s3 URL, " +
                "or by setting the " +
                "aws.access.key.id or " +                
                "aws.access.key.secret properties (respectively).");
        } else if (accessKey == null) {
          throw new IllegalArgumentException("AWS " +
                "Access Key ID must be specified " +
                "as the username of a s3 URL, or by setting the " +
                "aws.access.key.id property.");
        } else if (secretAccessKey == null) {
          throw new IllegalArgumentException("AWS " +
                "Secret Access Key must be specified " +
                "as the password of a s3 URL, or by setting the " +
                "aws.access.key.secret property.");        
        }
        
        RestS3Service s3Service;
        try {
            s3Service = new RestS3Service(
                new AWSCredentials(accessKey, secretAccessKey));
        } catch (S3ServiceException e) {
            e.printStackTrace();
            throw new IOException(e.toString());
        }
        InputStream is = null;
        try {
            // This opens the stream to the bucket/key object.
            S3Object s3obj = s3Service.getObject(new S3Bucket(u.getHost()),
                u.getPath().substring(1) /* Skip starting '/' character */);
            is = s3obj.getDataInputStream();
        } catch (S3ServiceException e) {
            e.printStackTrace();
            throw new IOException(e.toString());
        }

        final InputStream inputStream = is;
        return new URLConnection(u) {
            private InputStream is = inputStream;
            @Override
            public InputStream getInputStream() throws IOException {
                return this.is;
            }
            @Override
            public void connect() throws IOException {
                // Nothing to do. When we give back this object, we're
                // connected.
            }
        };
    }

    /**
     * Main dumps rsync file to STDOUT.
     * @param args
     * @throws IOException
     */
    public static void main(String[] args)
    throws IOException {
        if (args.length != 1) {
            System.out.println("Usage: java " +
                "org.archive.net.s3.Handler " +
                "s3://AWS_ACCESS_KEY_ID:AWS_ACCESS_KEY_SECRET@BUCKET/KEY");
            System.exit(1);
        }
        URL u = new URL(args[0]);
        URLConnection connect = u.openConnection();
        // Write download to stdout.
        final int bufferlength = 4096;
        byte [] buffer = new byte [bufferlength];
        InputStream is = connect.getInputStream();
        try {
            for (int count = -1;
                    (count = is.read(buffer, 0, bufferlength)) != -1;) {
                System.out.write(buffer, 0, count);
            }
            System.out.flush();
        } finally {
            is.close();
        }
    }
}