/*
* Copyright 2000-2001,2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jetspeed.util;
import java.io.InputStream;
import java.io.IOException;
import java.util.zip.Adler32;
import java.util.zip.CheckedInputStream;
/**
* implements checksum related utilities
*
* @author <a href="mailto:taylor@apache.org">David Sean Taylor </a>
* @version $Id: ChecksumHelper.java 187214 2004-08-05 18:26:19Z taylor $
*/
public final class ChecksumHelper
{
public static long getChecksum(InputStream is)
{
CheckedInputStream cis = null;
long checksum = 0;
try
{
cis = new CheckedInputStream(is, new Adler32());
byte[] tempBuf = new byte[128];
while (cis.read(tempBuf) >= 0)
{
}
checksum = cis.getChecksum().getValue();
}
catch (IOException e)
{
checksum = 0;
}
finally
{
if (cis != null)
{
try
{
cis.close();
}
catch (IOException ioe)
{
}
}
}
return checksum;
}
}