/*
* 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.wicket.markup.transformer;
import org.apache.wicket.Component;
import org.apache.wicket.MarkupContainer;
import org.apache.wicket.WicketRuntimeException;
import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.MarkupStream;
import org.apache.wicket.model.IModel;
import org.apache.wicket.request.Response;
import org.apache.wicket.response.StringResponse;
/**
* This abstract container provides the means to post-process the markup generated by its child
* components (excluding the containers tag)
* <p>
* Please see {@link org.apache.wicket.markup.transformer.AbstractTransformerBehavior} for an alternative
* based on {@link org.apache.wicket.behavior.Behavior}
*
* @see org.apache.wicket.markup.transformer.AbstractTransformerBehavior
* @see org.apache.wicket.markup.transformer.ITransformer
*
* @author Juergen Donnerstag
* */
public abstract class AbstractOutputTransformerContainer extends MarkupContainer
implements
ITransformer
{
private static final long serialVersionUID = 1L;
/** Whether the containers tag shall be transformed as well */
private boolean transformBodyOnly = true;
/**
* Construct
*
* @see org.apache.wicket.Component#Component(String)
*/
public AbstractOutputTransformerContainer(final String id)
{
super(id);
}
/**
* Construct
*
* @see org.apache.wicket.Component#Component(String, IModel)
*/
public AbstractOutputTransformerContainer(final String id, final IModel<?> model)
{
super(id, model);
}
/**
* You can choose whether the body of the tag excluding the tag shall be transformed or
* including the tag.
*
* @param value
* If true, only the body is applied to transformation.
* @return this
*/
public MarkupContainer setTransformBodyOnly(final boolean value)
{
transformBodyOnly = value;
return this;
}
/**
* Create a new response object which is used to store the markup generated by the child
* objects.
*
* @return Response object. Must not be null
*/
protected Response newResponse()
{
return new StringResponse();
}
@Override
public abstract CharSequence transform(final Component component, final CharSequence output)
throws Exception;
@Override
public final void onComponentTagBody(final MarkupStream markupStream, final ComponentTag openTag)
{
if (transformBodyOnly == true)
{
execute(new Runnable()
{
@Override
public void run()
{
// Invoke default execution
AbstractOutputTransformerContainer.super.onComponentTagBody(markupStream,
openTag);
}
});
}
else
{
super.onComponentTagBody(markupStream, openTag);
}
}
@Override
protected final void onRender()
{
if (transformBodyOnly == false)
{
execute(new Runnable()
{
@Override
public void run()
{
// Invoke default execution
AbstractOutputTransformerContainer.super.onRender();
}
});
}
else
{
super.onRender();
}
}
/**
*
* @param code
*/
private void execute(final Runnable code)
{
// Temporarily replace the web response with a String response
final Response webResponse = getResponse();
try
{
// Create a new response object
final Response response = newResponse();
if (response == null)
{
throw new IllegalStateException("newResponse() must not return null");
}
// and make it the current one
getRequestCycle().setResponse(response);
// Invoke default execution
code.run();
try
{
// Tranform the data
CharSequence output = transform(this, response.toString());
webResponse.write(output);
}
catch (Exception ex)
{
throw new WicketRuntimeException("Error while transforming the output: " + this, ex);
}
}
finally
{
// Restore the original response
getRequestCycle().setResponse(webResponse);
}
}
}