// Copyright 2013 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.tapestry5.internal.webresources;
import org.apache.tapestry5.ioc.Resource;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.Adler32;
/**
* @since 5.4
*/
public class ResourceTransformUtils
{
private static final double NANOS_TO_MILLIS = 1.0d / 1000000.0d;
public static double nanosToMillis(long nanos)
{
return ((double) nanos) * NANOS_TO_MILLIS;
}
public static long toChecksum(Resource resource)
{
Adler32 checksum = new Adler32();
byte[] buffer = new byte[1024];
InputStream is = null;
try
{
is = resource.openStream();
while (true)
{
int length = is.read(buffer);
if (length < 0)
{
break;
}
checksum.update(buffer, 0, length);
}
is.close();
// Reduces it down to just 32 bits which we express in hex.'
return checksum.getValue();
} catch (IOException ex)
{
throw new RuntimeException(ex);
}
}
}