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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
* . pas le cas, consultez :
* .
*
* $Revision: 5 $
*
************************************************************************
*/
package ca.nrc.cadc.io;
import java.io.IOException;
import java.io.InputStream;
/**
* Simple wrapper that keeps track of bytes read from the input stream.
*
* If a limit is provided, a ByteLimitExceededException will be thrown if that
* limit is reached.
*
* @version $Version$
* @author majorb
*/
public class ByteCountInputStream extends InputStream implements ByteCounter {
private InputStream inputStream;
private long byteCount = 0L;
private Long byteLimit = null;
/**
* Constructor that takes the target input stream..
*
* @param inputStream The InputStream to wrap.
*/
public ByteCountInputStream(final InputStream inputStream) {
this.inputStream = inputStream;
}
/**
* Constructor that takes the target input stream and a byte limit.
*
* @param inputStream The InputStream to wrap.
* @param byteLimit The limit to the number of bytes to read.
*/
public ByteCountInputStream(final InputStream inputStream, final long byteLimit) {
this.inputStream = inputStream;
if (byteLimit > 0) {
this.byteLimit = byteLimit;
}
}
/**
* Return the number of bytes that were read.
*/
@Override
public long getByteCount() {
return byteCount;
}
/**
* The quota space left to be written to.
*
* @return Quota space left, in bytes.
*/
public Long getByteLimit() {
return byteLimit;
}
@Override
public int available() throws IOException {
return inputStream.available();
}
@Override
public void close() throws IOException {
inputStream.close();
}
@Override
public void mark(int readlimit) {
inputStream.mark(readlimit);
}
@Override
public boolean markSupported() {
return inputStream.markSupported();
}
@Override
public int read() throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
int value = inputStream.read();
byteCount++;
return value;
}
@Override
public int read(byte[] b) throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
int bytesRead = inputStream.read(b);
if (bytesRead != -1) {
byteCount += bytesRead;
}
return bytesRead;
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
if (hasReachedLimit()) {
throw new ByteLimitExceededException(byteLimit);
}
int bytesRead = inputStream.read(b, off, len);
if (bytesRead != -1) {
byteCount += bytesRead;
}
return bytesRead;
}
/**
* Reset this stream, if supported.
*
* @throws IOException If not supported, or something went wrong.
*
*/
@Override
public void reset() throws IOException {
inputStream.reset();
byteCount = 0;
}
@Override
public long skip(long n) throws IOException {
return inputStream.skip(n);
}
/**
* Obtain whether the byte limit has been reached.
*/
private boolean hasReachedLimit() {
if (byteLimit == null) {
return false;
}
return byteCount >= byteLimit;
}
}