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/*
************************************************************************
******************* CANADIAN ASTRONOMY DATA CENTRE *******************
************** CENTRE CANADIEN DE DONNÉES ASTRONOMIQUES **************
*
* (c) 2016. (c) 2016.
* Government of Canada Gouvernement du Canada
* National Research Council Conseil national de recherches
* Ottawa, Canada, K1A 0R6 Ottawa, Canada, K1A 0R6
* All rights reserved Tous droits réservés
*
* NRC disclaims any warranties, Le CNRC dénie toute garantie
* expressed, implied, or énoncée, implicite ou légale,
* statutory, of any kind with de quelque nature que ce
* respect to the software, soit, concernant le logiciel,
* including without limitation y compris sans restriction
* any warranty of merchantability toute garantie de valeur
* or fitness for a particular marchande ou de pertinence
* purpose. NRC shall not be pour un usage particulier.
* liable in any event for any Le CNRC ne pourra en aucun cas
* damages, whether direct or être tenu responsable de tout
* indirect, special or general, dommage, direct ou indirect,
* consequential or incidental, particulier ou général,
* arising from the use of the accessoire ou fortuit, résultant
* software. Neither the name de l'utilisation du logiciel. Ni
* of the National Research le nom du Conseil National de
* Council of Canada nor the Recherches du Canada ni les noms
* names of its contributors may de ses participants ne peuvent
* be used to endorse or promote être utilisés pour approuver ou
* products derived from this promouvoir les produits dérivés
* software without specific prior de ce logiciel sans autorisation
* written permission. préalable et particulière
* par écrit.
*
* This file is part of the Ce fichier fait partie du projet
* OpenCADC project. OpenCADC.
*
* OpenCADC is free software: OpenCADC est un logiciel libre ;
* you can redistribute it and/or vous pouvez le redistribuer ou le
* modify it under the terms of modifier suivant les termes de
* the GNU Affero General Public la “GNU Affero General Public
* License as published by the License” telle que publiée
* Free Software Foundation, par la Free Software Foundation
* either version 3 of the : soit la version 3 de cette
* License, or (at your option) licence, soit (à votre gré)
* any later version. toute version ultérieure.
*
* OpenCADC is distributed in the OpenCADC est distribué
* hope that it will be useful, dans l’espoir qu’il vous
* but WITHOUT ANY WARRANTY; sera utile, mais SANS AUCUNE
* without even the implied GARANTIE : sans même la garantie
* warranty of MERCHANTABILITY implicite de COMMERCIALISABILITÉ
* or FITNESS FOR A PARTICULAR ni d’ADÉQUATION À UN OBJECTIF
* PURPOSE. See the GNU Affero PARTICULIER. Consultez la Licence
* General Public License for Générale Publique GNU Affero
* more details. pour plus de détails.
*
* You should have received Vous devriez avoir reçu une
* a copy of the GNU Affero copie de la Licence Générale
* General Public License along Publique GNU Affero avec
* with OpenCADC. If not, see OpenCADC ; si ce n’est
* Alternate constructors allow for byte limits to be set and for the lazy
* retrieval of the output stream from an HttpServletResponse object.
*
* @author pdowler
*/
public class ByteCountOutputStream extends OutputStream implements ByteCounter {
private OutputStream ostream;
private long byteCount = 0L;
private Long byteLimit = null;
/**
* Constructor.
*
* @param outputStream
*/
public ByteCountOutputStream(OutputStream outputStream) {
super();
this.ostream = outputStream;
}
/**
* Constructor that takes the target output stream and a byte limit.
*
* @param outputStream The OutputStream to wrap.
* @param byteLimit The quota space left to be written to, in bytes.
*/
public ByteCountOutputStream(OutputStream outputStream, long byteLimit) {
this.ostream = outputStream;
if (byteLimit > 0) {
this.byteLimit = byteLimit;
}
}
/**
* Get the number of bytes written to the underlying output stream to far. This
* value is up to date right after flush() is called; otherwise, it may be less
* than the total number of bytes written via write() method calls of the
* underlying stream.
*
* @return number of bytes written to underlying output stream
*/
@Override
public long getByteCount() {
return byteCount;
}
@Override
public void close() throws IOException {
ostream.close();
}
@Override
public void flush() throws IOException {
ostream.flush();
}
@Override
public void write(int b) throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
ostream.write(b);
byteCount++;
}
@Override
public void write(byte[] b) throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
ostream.write(b);
byteCount += b.length;
}
@Override
public void write(byte[] b, int offset, int num) throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
ostream.write(b, offset, num);
byteCount += num;
}
/**
* Obtain whether the byte limit has been reached.
*/
private boolean hasReachedLimit() {
if (byteLimit == null) {
return false;
}
return byteCount >= byteLimit;
}
}