/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.myfaces.trinidadinternal.image.cache;
import java.io.InputStream;
import java.io.IOException;
import java.util.Map;
import org.apache.myfaces.trinidad.logging.TrinidadLogger;
import org.apache.myfaces.trinidad.share.io.InputStreamProvider;
import org.apache.myfaces.trinidadinternal.image.ImageConstants;
import org.apache.myfaces.trinidadinternal.image.ImageContext;
import org.apache.myfaces.trinidadinternal.image.ImageProviderRequest;
/**
* Cache entry data structure which checks to see if the source
* icon has changed.
* @version $Name: $ ($Revision: adfrt/faces/adf-faces-impl/src/main/java/oracle/adfinternal/view/faces/image/cache/SourceCheckingCacheEntry.java#0 $) $Date: 10-nov-2005.19:06:12 $
*/
class SourceCheckingCacheEntry extends CacheEntry
{
public SourceCheckingCacheEntry(
String uri,
int width,
int height,
String encoding
)
{
super(uri, width, height, encoding);
}
@Override
public boolean isValid(
ImageContext context,
ImageProviderRequest request
)
{
// Make sure we have an InputStreamProvider for the source
// icon. We need this to check for modifications
if (_provider == _NULL_PROVIDER)
return true;
InputStreamProvider provider = (InputStreamProvider)_provider;
if (provider == null)
{
provider = _getInputStreamProvider(context, request);
if (provider == null)
{
_provider = _NULL_PROVIDER;
return true;
}
_provider = provider;
}
return !provider.hasSourceChanged();
}
// Gets the source icon InputStreamProvider for the current request
private static InputStreamProvider _getInputStreamProvider(
ImageContext context,
ImageProviderRequest request
)
{
Map<Object, Object> properties = request.getRenderProperties(context);
assert (properties != null);
InputStreamProvider provider = (InputStreamProvider)properties.get(
ImageConstants.SOURCE_INPUT_STREAM_PROVIDER_KEY);
if (provider == null)
return null;
// We need to actually open the input stream in order
// to establish the original last modified time
try
{
InputStream in = provider.openInputStream();
in.close();
}
catch (IOException e)
{
_LOG.severe(e);
return null;
}
return provider;
}
private Object _provider;
private static final Object _NULL_PROVIDER = new Object();
private static final TrinidadLogger _LOG = TrinidadLogger.createTrinidadLogger(SourceCheckingCacheEntry.class);
}