eu.europa.esig.dss.client.http.NativeHTTPDataLoader.java Source code

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Here is the source code for eu.europa.esig.dss.client.http.NativeHTTPDataLoader.java

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/**
 * DSS - Digital Signature Services
 * Copyright (C) 2015 European Commission, provided under the CEF programme
 *
 * This file is part of the "DSS - Digital Signature Services" project.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */
package eu.europa.esig.dss.client.http;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.NotImplementedException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import eu.europa.esig.dss.DSSCannotFetchDataException;
import eu.europa.esig.dss.DSSException;
import eu.europa.esig.dss.DSSCannotFetchDataException.MSG;

/**
 * Implementation of HTTPDataLoader that use the java.net.URL class.
 *
 */
public class NativeHTTPDataLoader implements DataLoader {

    private static Logger logger = LoggerFactory.getLogger(NativeHTTPDataLoader.class);

    private static final long MAX_SIZE = 15000;

    /**
     * Used to limit the size of fetched data.
     */
    private class MaxSizeInputStream extends InputStream {

        private long maxSize;

        private InputStream wrappedStream;

        private long count = 0;

        private String url;

        /**
         * The default constructor for NativeHTTPDataLoader.MaxSizeInputStream.
         */
        public MaxSizeInputStream(InputStream wrappedStream, long maxSize, String url) {
            this.maxSize = maxSize;
            this.wrappedStream = wrappedStream;
            this.url = url;
        }

        @Override
        public int read() throws IOException {
            if (maxSize != 0) {
                count++;
                if (count > maxSize) {
                    throw new DSSCannotFetchDataException(MSG.SIZE_LIMIT_EXCEPTION, url);
                }
            }
            return wrappedStream.read();
        }

    }

    @Override
    public byte[] get(String url) {
        InputStream inputStream = null;
        byte[] result = null;
        try {
            inputStream = new MaxSizeInputStream(new URL(url).openStream(), MAX_SIZE, url);
            result = IOUtils.toByteArray(inputStream);
        } catch (IOException e) {
            throw new DSSException("An error occured while HTTP GET for url '" + url + "' : " + e.getMessage(), e);
        } finally {
            IOUtils.closeQuietly(inputStream);
        }
        return result;
    }

    @Override
    public byte[] post(String url, byte[] content) {
        OutputStream out = null;
        InputStream inputStream = null;
        byte[] result = null;
        try {
            URLConnection connection = new URL(url).openConnection();

            connection.setDoInput(true);
            connection.setDoOutput(true);
            connection.setUseCaches(false);

            out = connection.getOutputStream();
            IOUtils.write(content, out);
            inputStream = connection.getInputStream();
            result = IOUtils.toByteArray(inputStream);
        } catch (IOException e) {
            throw new DSSException("An error occured while HTTP POST for url '" + url + "' : " + e.getMessage(), e);
        } finally {
            IOUtils.closeQuietly(out);
            IOUtils.closeQuietly(inputStream);
        }
        return result;
    }

    @Override
    public DataAndUrl get(List<String> urlStrings) {

        final int numberOfUrls = urlStrings.size();
        int ii = 0;
        for (final String urlString : urlStrings) {
            try {

                ii++;
                final byte[] bytes = get(urlString);
                if (bytes == null) {
                    continue;
                }
                return new DataAndUrl(bytes, urlString);
            } catch (Exception e) {
                if (ii == numberOfUrls) {
                    if (e instanceof DSSException) {
                        throw (DSSException) e;
                    }
                    throw new DSSException(e);
                }
                logger.warn("Impossible to obtain data using {}", urlString, e);
            }
        }
        return null;
    }

    @Override
    public byte[] get(String url, boolean refresh) {
        // set cache = false;
        return get(url);
    }

    @Override
    public void setContentType(String contentType) {
        throw new NotImplementedException();
    }

}