/*
* FormatIdentifier.java
*
* Version: $Revision: 3761 $
*
* Date: $Date: 2009-05-07 04:18:02 +0000 (Thu, 07 May 2009) $
*
* Copyright (c) 2002-2009, The DSpace Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the DSpace Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*/
package org.dspace.content;
import java.sql.SQLException;
import org.dspace.core.Context;
import org.dspace.storage.rdbms.DatabaseManager;
import org.dspace.storage.rdbms.TableRowIterator;
/**
* This class handles the recognition of bitstream formats, using the format
* registry in the database. For the moment, the format identifier simply uses
* file extensions stored in the "BitstreamFormatIdentifier" table. This
* probably isn't a particularly satisfactory long-term solution.
*
* @author Robert Tansley
* @version $Revision: 3761 $
*/
public class FormatIdentifier
{
/**
* Attempt to identify the format of a particular bitstream. If the format
* is unknown, null is returned.
*
* @param bitstream
* the bitstream to identify the format of
*
* @return a format from the bitstream format registry, or null
*/
public static BitstreamFormat guessFormat(Context context,
Bitstream bitstream) throws SQLException
{
// FIXME: Just setting format to first guess
// For now just get the file name
String filename = bitstream.getName().toLowerCase();
// Gracefully handle the null case
if (filename == null)
{
return null;
}
// This isn't rocket science. We just get the name of the
// bitstream, get the extension, and see if we know the type.
String extension = filename;
int lastDot = filename.lastIndexOf('.');
if (lastDot != -1)
{
extension = filename.substring(lastDot + 1);
}
// If the last character was a dot, then extension will now be
// an empty string. If this is the case, we don't know what
// file type it is.
if (extension.equals(""))
{
return null;
}
// See if the extension is in the fileextension table
TableRowIterator tri = DatabaseManager.query(context,
"SELECT bitstreamformatregistry.* FROM bitstreamformatregistry, " +
"fileextension WHERE fileextension.extension LIKE ? " +
"AND bitstreamformatregistry.bitstream_format_id=" +
"fileextension.bitstream_format_id",
extension);
BitstreamFormat retFormat = null;
try
{
if (tri.hasNext())
{
// Return first match
retFormat = new BitstreamFormat(context, tri.next());
}
else
{
retFormat = null;
}
}
finally
{
// close the TableRowIterator to free up resources
if (tri != null)
tri.close();
}
return retFormat;
}
}