org.apache.myfaces.custom.graphicimagedynamic.GraphicImageDynamicRenderer Maven / Gradle / Ivy
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* 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.custom.graphicimagedynamic;
import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import javax.faces.FacesException;
import javax.faces.FactoryFinder;
import javax.faces.component.UIComponent;
import javax.faces.component.UIParameter;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.faces.context.FacesContextFactory;
import javax.faces.context.ResponseStream;
import javax.faces.context.ResponseWriter;
import javax.faces.lifecycle.Lifecycle;
import javax.faces.lifecycle.LifecycleFactory;
import javax.faces.webapp.FacesServlet;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.myfaces.component.html.util.ParameterResourceHandler;
import org.apache.myfaces.shared_tomahawk.renderkit.RendererUtils;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HtmlRendererUtils;
import org.apache.myfaces.renderkit.html.ext.HtmlImageRenderer;
import org.apache.myfaces.renderkit.html.util.AddResource;
import org.apache.myfaces.renderkit.html.util.AddResourceFactory;
import org.apache.myfaces.renderkit.html.util.ResourceLoader;
import org.apache.myfaces.shared_tomahawk.util.ClassUtils;
/**
* @author Sylvain Vieujot
* @version $Revision: 472727 $ $Date: 2005-05-23 19:39:37 +0200 (Mon, 23 May 2005) $
*/
public class GraphicImageDynamicRenderer extends HtmlImageRenderer implements ResourceLoader
{
protected static class SimpleImageContext implements ImageContext
{
private final Map _params;
private final Integer _width;
private final Integer _height;
public SimpleImageContext(Map params, Integer width, Integer height)
{
_params = params;
_width = width;
_height = height;
}
public Map getParamters()
{
return _params;
}
public Integer getWidth()
{
return _width;
}
public Integer getHeight()
{
return _height;
}
}
private static final Log log = LogFactory.getLog(GraphicImageDynamicRenderer.class);
private static final class ImageResponseStream extends ResponseStream
{
private final OutputStream _out;
private ImageResponseStream(OutputStream out)
{
_out = out;
}
public void close() throws IOException
{
_out.flush();
_out.close();
}
public void flush() throws IOException
{
_out.flush();
}
public void write(byte[] b, int off, int len) throws IOException
{
_out.write(b, off, len);
}
public void write(byte[] b) throws IOException
{
_out.write(b);
}
public void write(int b) throws IOException
{
_out.write(b);
}
}
private static final String RENDERER_PARAM = "_renderer";
private static final String WIDTH_PARAM = "_width";
private static final String HEIGHT_PARAM = "_height";
public static final String RENDERER_TYPE = "org.apache.myfaces.GraphicImageDynamicRenderer";
public void encodeEnd(FacesContext context, UIComponent component) throws IOException
{
RendererUtils.checkParamValidity(context, component, GraphicImageDynamic.class);
GraphicImageDynamic graphicImageDynamic = (GraphicImageDynamic) component;
ResponseWriter writer = context.getResponseWriter();
writer.startElement(HTML.IMG_ELEM, graphicImageDynamic);
HtmlRendererUtils.writeIdIfNecessary(writer, graphicImageDynamic, context);
HtmlRendererUtils.renderHTMLAttributes(writer, graphicImageDynamic,
HTML.IMG_PASSTHROUGH_ATTRIBUTES);
Map params = getParameterMap(context, component);
String width = graphicImageDynamic.getWidth();
if (width != null)
{
params.put(WIDTH_PARAM, width);
}
String height = graphicImageDynamic.getHeight();
if (height != null)
{
params.put(HEIGHT_PARAM, height);
}
Class imageRendererClass = graphicImageDynamic.getImageRendererClass();
if (imageRendererClass == null)
{
throw new FacesException("No imageRendererClass defined for component "
+ component.getId());
}
params.put(RENDERER_PARAM, imageRendererClass.getName());
AddResource addResource = AddResourceFactory.getInstance(context);
String url = addResource.getResourceUri(context, new ParameterResourceHandler(this
.getClass(), params));
writer.writeAttribute(HTML.SRC_ATTR, url, null);
writer.endElement(HTML.IMG_ELEM);
}
protected Map getParameterMap(FacesContext context, UIComponent component)
{
Map result = new HashMap();
for (Iterator iter = component.getChildren().iterator(); iter.hasNext();)
{
UIComponent child = (UIComponent) iter.next();
if (child instanceof UIParameter)
{
UIParameter uiparam = (UIParameter) child;
Object value = uiparam.getValue();
if (value != null)
{
result.put(uiparam.getName(), value);
}
}
}
return result;
}
public void decode(FacesContext facesContext, UIComponent component)
{
super.decode(facesContext, component);
}
/**
* @throws IOException
* @see org.apache.myfaces.renderkit.html.util.ResourceLoader#serveResource(javax.servlet.ServletContext, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, java.lang.String)
*/
public void serveResource(ServletContext context, HttpServletRequest request,
HttpServletResponse response, String resourceUri) throws IOException
{
FacesContextFactory facesContextFactory = (FacesContextFactory) FactoryFinder
.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);
LifecycleFactory lifecycleFactory = (LifecycleFactory) FactoryFinder
.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
Lifecycle lifecycle = lifecycleFactory.getLifecycle(getLifecycleId(context));
FacesContext facesContext = facesContextFactory.getFacesContext(context, request, response,
lifecycle);
facesContext.setResponseStream(new ImageResponseStream(response.getOutputStream()));
try
{
Map requestMap = facesContext.getExternalContext().getRequestParameterMap();
Object rendererValue = requestMap.get(RENDERER_PARAM);
if (rendererValue == null)
{
throw new FacesException("no image renderer defined.");
}
try
{
Class rendererClass = ClassUtils.classForName(rendererValue.toString());
if (!ImageRenderer.class.isAssignableFrom(rendererClass))
{
throw new FacesException("Image renderer class [" + rendererValue
+ "] does not implement " + ImageRenderer.class.getName());
}
try
{
ImageRenderer imageRenderer = (ImageRenderer) rendererClass.newInstance();
renderImage(imageRenderer, facesContext);
}
catch (InstantiationException e)
{
throw new FacesException("could not instantiate image renderer class "
+ rendererValue + " : " + e.getMessage(), e);
}
catch (IllegalAccessException e)
{
throw new FacesException("could not instantiate image renderer class "
+ rendererValue + " : " + e.getMessage(), e);
}
catch (Exception e)
{
throw new FacesException("could not renderer image "
+ rendererValue + " : " + e.getMessage(), e);
}
}
catch (ClassNotFoundException e)
{
throw new FacesException("image renderer class not found: " + e.getMessage(), e);
}
facesContext.getResponseStream().close();
}
finally
{
facesContext.release();
}
}
protected void renderImage(ImageRenderer imageRenderer, FacesContext facesContext)
throws Exception
{
ImageContext imageContext = createImageContext(facesContext);
imageRenderer.setContext(facesContext, imageContext);
HttpServletResponse response = (HttpServletResponse) facesContext.getExternalContext()
.getResponse();
int contentLength = imageRenderer.getContentLength();
if( contentLength >0 )
{
response.setContentLength(contentLength);
}
String contentType = imageRenderer.getContentType();
if (contentType != null && contentType.length() > 0 )
{
response.setContentType(contentType);
}
ResponseStream out = facesContext.getResponseStream();
try
{
imageRenderer.renderResource( out );
}
finally
{
out.close();
facesContext.responseComplete();
}
}
protected ImageContext createImageContext(FacesContext facesContext)
{
ExternalContext externalContext = facesContext.getExternalContext();
final Map requestMap = externalContext.getRequestParameterMap();
Object value = requestMap.get(WIDTH_PARAM);
Integer width = null;
if (value != null)
{
try
{
width = Integer.valueOf(value.toString());
}
catch (NumberFormatException e)
{
log.error("Invalid value for image width : " + value + ", " + e.getMessage(), e);
}
}
Integer height = null;
value = requestMap.get(HEIGHT_PARAM);
if (value != null)
{
try
{
height = Integer.valueOf(value.toString());
}
catch (NumberFormatException e)
{
log.error("Invalid value for image height : " + value + ", " + e.getMessage(), e);
}
}
return new SimpleImageContext(requestMap, width, height);
}
private String getLifecycleId(ServletContext context)
{
String lifecycleId = context.getInitParameter(FacesServlet.LIFECYCLE_ID_ATTR);
return lifecycleId != null ? lifecycleId : LifecycleFactory.DEFAULT_LIFECYCLE;
}
}
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