de.kapsi.net.daap.DaapHeaderConstructor.java Source code

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Here is the source code for de.kapsi.net.daap.DaapHeaderConstructor.java

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/* 
 * Digital Audio Access Protocol (DAAP)
 * Copyright (C) 2004 Roger Kapsi, info at kapsi dot de
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package de.kapsi.net.daap;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.io.ByteArrayOutputStream;

import java.util.ArrayList;

import org.apache.commons.httpclient.Header;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * A helper class to create easily misc DAAP response header
 *
 * @author  Roger Kapsi
 */
public class DaapHeaderConstructor {

    private static final Log LOG = LogFactory.getLog(DaapHeaderConstructor.class);

    private static final byte[] CRLF = { (byte) '\r', (byte) '\n' };
    private static final String ISO_8859_1 = "8859_1";

    private static final String HTTP_OK = "HTTP/1.1 200 OK";
    private static final String HTTP_AUTH = "HTTP/1.1 401 Authorization Required";
    private static final String HTTP_PARTIAL_CONTENT = "HTTP/1.1 206 Partial Content";

    /**
     * Creates a new Chunk Header
     *
     * @param request
     * @param contentLength
     * @return
     */
    public static byte[] createChunkHeader(DaapRequest request, int contentLength) {

        try {

            DaapConnection connection = request.getConnection();
            String serverName = connection.getServer().getConfig().getServerName();

            ArrayList headers = new ArrayList();
            headers.add(new Header("Date", DaapUtil.now()));
            headers.add(new Header("DAAP-Server", serverName));
            headers.add(new Header("Content-Type", "application/x-dmap-tagged"));
            headers.add(new Header("Content-Length", Integer.toString(contentLength)));

            if (DaapUtil.COMPRESS) {
                headers.add(new Header("Content-Encoding", "gzip"));
            }

            return toByteArray(HTTP_OK, (Header[]) headers.toArray(new Header[0]));

        } catch (UnsupportedEncodingException err) {
            // Should never happen
            throw new RuntimeException(err);

        } catch (IOException err) {
            // Should never happen
            throw new RuntimeException(err);
        }
    }

    /**
     * Creates an Audio Header
     *
     * @param request
     * @param contentLength
     * @return
     */
    public static byte[] createAudioHeader(DaapRequest request, int pos, int end, int contentLength) {

        try {

            DaapConnection connection = request.getConnection();
            int version = connection.getProtocolVersion();

            if (version == DaapUtil.NULL)
                throw new IOException("Client Protocol Version is unknown");

            String serverName = connection.getServer().getConfig().getServerName();

            String statusLine = null;

            ArrayList headers = new ArrayList();

            headers.add(new Header("Date", DaapUtil.now()));
            headers.add(new Header("DAAP-Server", serverName));
            headers.add(new Header("Content-Type", "application/x-dmap-tagged"));

            // 
            if (pos == 0 || version <= DaapUtil.VERSION_2) {

                statusLine = HTTP_OK;
                headers.add(new Header("Content-Length", Integer.toString(contentLength)));

            } else {

                statusLine = HTTP_PARTIAL_CONTENT;

                String cotentLengthStr = Integer.toString(contentLength - pos);
                String contentRange = "bytes " + pos + "-" + (contentLength - 1) + "/" + contentLength;
                headers.add(new Header("Content-Length", cotentLengthStr));
                headers.add(new Header("Content-Range", contentRange));
            }

            headers.add(new Header("Accept-Ranges", "bytes"));

            return toByteArray(statusLine, (Header[]) headers.toArray(new Header[0]));

        } catch (UnsupportedEncodingException err) {
            // Should never happen
            throw new RuntimeException(err);

        } catch (IOException err) {
            // Should never happen
            throw new RuntimeException(err);
        }
    }

    /**
     * Creates a new Authentication Header
     *
     * @param request
     * @return
     */
    public static byte[] createAuthHeader(DaapRequest request) {

        try {

            DaapConnection connection = request.getConnection();
            String serverName = connection.getServer().getConfig().getServerName();

            ArrayList headers = new ArrayList();

            headers.add(new Header("Date", DaapUtil.now()));
            headers.add(new Header("DAAP-Server", serverName));
            headers.add(new Header("Content-Type", "text/html"));
            headers.add(new Header("Content-Length", "0"));
            //                headers.add(new Header("WWW-Authenticate", "Basic-realm=\"daap\""));

            return toByteArray(HTTP_AUTH, (Header[]) headers.toArray(new Header[0]));

        } catch (UnsupportedEncodingException err) {
            // Should never happen
            throw new RuntimeException(err);

        } catch (IOException err) {
            // Should never happen
            throw new RuntimeException(err);
        }
    }

    /**
     * Converts statusLine and headers to an byte-Array
     */
    private static byte[] toByteArray(String statusLine, Header[] headers)
            throws UnsupportedEncodingException, IOException {

        ByteArrayOutputStream out = new ByteArrayOutputStream();

        out.write(statusLine.getBytes(ISO_8859_1));
        out.write(CRLF);

        for (int i = 0; i < headers.length; i++) {
            out.write(headers[i].toExternalForm().getBytes(ISO_8859_1));
        }

        out.write(CRLF);
        out.close();

        return out.toByteArray();
    }

    /** Creates a new instance of DaapHeaderConstructor */
    private DaapHeaderConstructor() {
    }
}