package it.unimi.dsi.mg4j.query;
/*
* MG4J: Managing Gigabytes for Java
*
* Copyright (C) 2005-2010 Sebastiano Vigna
*
* 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, see <http://www.gnu.org/licenses/>.
*
*/
import it.unimi.dsi.Util;
import it.unimi.dsi.mg4j.document.DocumentCollection;
import java.io.IOException;
import java.io.InputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;
/** An item serving a raw input stream from the document collection.
*
* <P>This kind of {@link it.unimi.dsi.mg4j.query.QueryServlet} item will load into the browser
* the stream returned by the document collection for the given document. Using the system property
* <samp>it.unimi.dsi.mg4j.query.InputStreamItem.skip</samp>, you can set a number of sub-input streams
* that will be skipped by calling {@link java.io.InputStream#reset()} (see {@link it.unimi.dsi.mg4j.document}).
*/
public class InputStreamItem extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final Logger LOGGER = Util.getLogger( InputStreamItem.class );
private static final int skip = Integer.getInteger( InputStreamItem.class.getName() + ".skip", 0 ).intValue();
protected void doGet( final HttpServletRequest request, final HttpServletResponse response ) throws IOException {
try {
if ( request.getParameter( "m" ) != null && request.getParameter( "doc" ) != null ) {
DocumentCollection collection = (DocumentCollection)getServletContext().getAttribute( "collection" );
if ( collection == null ) LOGGER.fatal( "The servlet context does not contain a document collection." );
response.setContentType( request.getParameter( "m" ) );
response.setCharacterEncoding( "UTF-8" );
InputStream rawContent = collection.stream( Integer.parseInt( request.getParameter( "doc" ) ) );
for( int i = skip; i-- != 0; ) rawContent.reset();
IOUtils.copy( rawContent, response.getOutputStream() );
}
} catch( RuntimeException e ) {
e.printStackTrace();
LOGGER.error( e.toString() );
throw e;
}
}
protected void doPost( final HttpServletRequest request, final HttpServletResponse response ) throws IOException {
doGet( request, response );
}
}