/*
* 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.core.util.string;
import org.apache.wicket.Application;
import org.apache.wicket.Component;
import org.apache.wicket.MarkupContainer;
import org.apache.wicket.ThreadContext;
import org.apache.wicket.core.request.handler.PageProvider;
import org.apache.wicket.markup.IMarkupCacheKeyProvider;
import org.apache.wicket.markup.IMarkupResourceStreamProvider;
import org.apache.wicket.markup.MarkupNotFoundException;
import org.apache.wicket.markup.html.WebPage;
import org.apache.wicket.protocol.http.BufferedWebResponse;
import org.apache.wicket.request.Response;
import org.apache.wicket.request.cycle.RequestCycle;
import org.apache.wicket.util.resource.IResourceStream;
import org.apache.wicket.util.resource.StringResourceStream;
/**
* A helper class for rendering components and pages
*/
public class ComponentRenderer
{
/**
* Collects the html generated by the rendering of a page.
*
* @param pageProvider
* the provider of the page class/instance and its parameters
* @return the html rendered by a page
*/
public static CharSequence renderPage(final PageProvider pageProvider)
{
Application application = Application.get();
RequestCycle originalRequestCycle = RequestCycle.get();
BufferedWebResponse tempResponse = new BufferedWebResponse(null);
RequestCycle tempRequestCycle = application.createRequestCycle(originalRequestCycle.getRequest(), tempResponse);
try
{
ThreadContext.setRequestCycle(tempRequestCycle);
pageProvider.getPageInstance().renderPage();
}
finally
{
ThreadContext.setRequestCycle(originalRequestCycle);
}
return tempResponse.getText();
}
/**
* Collects the html generated by the rendering of a component.
*
* @param component
* the component to render.
* @return the html rendered by the component
*/
public static CharSequence renderComponent(final Component component)
{
RequestCycle requestCycle = RequestCycle.get();
final Response originalResponse = requestCycle.getResponse();
BufferedWebResponse tempResponse = new BufferedWebResponse(null);
MarkupContainer oldParent = component.getParent();
try
{
requestCycle.setResponse(tempResponse);
// add the component to a dummy page just for the rendering
RenderPage page = new RenderPage(component);
page.internalInitialize();
component.render();
}
finally
{
if (oldParent != null)
{
oldParent.add(component); // re-add the child to its old parent
}
requestCycle.setResponse(originalResponse);
}
return tempResponse.getText();
}
/**
* A page used as a parent for the component based rendering.
*/
private static class RenderPage extends WebPage implements IMarkupResourceStreamProvider, IMarkupCacheKeyProvider
{
/**
* Markup to use when the component to render is not already added to a MarkupContainer
*/
private static final String DEFAULT_MARKUP = "<wicket:container wicket:id='%s'></wicket:container>";
/**
* The markup of the component to render
*/
private final String markup;
private RenderPage(Component component)
{
// do not store the page in IPageStore/IDataStore. WICKET-5422
setStatelessHint(true);
String componentMarkup;
try
{
componentMarkup = component.getMarkup().toString(true);
} catch (MarkupNotFoundException mnfx)
{
componentMarkup = String.format(DEFAULT_MARKUP, component.getId());
}
this.markup = componentMarkup;
add(component); // this changes the component's parent
}
@Override
public IResourceStream getMarkupResourceStream(MarkupContainer container, Class<?> containerClass)
{
return new StringResourceStream(markup);
}
@Override
public String getCacheKey(MarkupContainer container, Class<?> containerClass)
{
// no caching for this page
return null;
}
@Override
public boolean isBookmarkable()
{
// pretend the page is bookmarkable to make it stateless. WICKET-5422
return true;
}
}
}