org.apache.tapestry.asset
Class ResourceChecksumSourceImpl

java.lang.Object
  org.apache.tapestry.asset.ResourceChecksumSourceImpl

All Implemented Interfaces:

ResourceChecksumSource

public class ResourceChecksumSourceImpl
extends Object
implements ResourceChecksumSource

Implementation of org.apache.tapestry.asset.ResourceDigestSource that calculates an checksum using a message digest and configured encoder. This code is based on code from Howard Lewis Ship from the upcoming 3.1 release.

Since:

3.0.3

Author:

Paul Ferraro

Constructor Summary

ResourceChecksumSourceImpl(String digestAlgorithm, org.apache.commons.codec.BinaryEncoder encoder)

Method Summary

protected String	computeChecksum(URL resourceURL) Computes a message digest of the specified resource and encodes it into a string.
String	getChecksum(URL resourceURL) Checksum is obtained from cache if possible.
void	reset() Clears the internal cache.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ResourceChecksumSourceImpl

public ResourceChecksumSourceImpl(String digestAlgorithm,
                                  org.apache.commons.codec.BinaryEncoder encoder)

Method Detail

getChecksum

public String getChecksum(URL resourceURL)

Checksum is obtained from cache if possible. If not, checksum is computed using computeChecksum(URL)

Specified by:

getChecksum in interface ResourceChecksumSource

Parameters:

resourceURL - the url of a resource

Returns:

the checksum value of the specified resource

See Also:

org.apache.tapestry.asset.ResourceDigestSource#getChecksum(java.net.URL)

reset

public void reset()

Description copied from interface: ResourceChecksumSource

Clears the internal cache.

Specified by:

reset in interface ResourceChecksumSource

See Also:

org.apache.tapestry.asset.ResourceDigestSource#reset()

computeChecksum

protected String computeChecksum(URL resourceURL)

Computes a message digest of the specified resource and encodes it into a string.

Parameters:

resourceURL - the url of a resource

Returns:

the checksum value of the specified resource