org.apache.wicket.markup.html
Class DynamicWebResource

java.lang.Object
  org.apache.wicket.Resource
      org.apache.wicket.markup.html.WebResource
          org.apache.wicket.markup.html.DynamicWebResource

All Implemented Interfaces:

Serializable, IClusterable, IRequestListener, IResourceListener

Direct Known Subclasses:

DynamicImageResource

public abstract class DynamicWebResource
extends WebResource

An WebResource subclass for dynamic resources (resources created programmatically).

This class caches the generated resource in memory, and is thus very useful for things you generate dynamically, but reuse for a while after that. If you need resources that stream directly and are not cached, extend WebResource directly and implement Resource.getResourceStream() yourself.

Author:

Jonathan Locke, Johan Compagner, Gili Tzabari

See Also:

Serialized Form

Nested Class Summary

static class

DynamicWebResource.ResourceState The resource state returned by the getResourceState() method.

Field Summary

Fields inherited from interface org.apache.wicket.IResourceListener

INTERFACE

Constructor Summary

DynamicWebResource()
Creates a dynamic resource.

DynamicWebResource(Locale locale)
Creates a dynamic resource from for the given locale

DynamicWebResource(Locale locale, String filename)
Creates a dynamic resource from for the given locale

DynamicWebResource(String filename)
Creates a dynamic resource.

Method Summary

Locale	getLocale() Returns the resource locale.
protected abstract DynamicWebResource.ResourceState	getResourceState() Gets the byte array for our dynamic resource.
IResourceStream	getResourceStream() Returns a new IResourceStream that provides all data for the request.
protected void	setHeaders(WebResponse response) Subclasses can override this to set there headers when the resource is being served.

Methods inherited from class org.apache.wicket.markup.html.WebResource

configureResponse, getCacheDuration

Methods inherited from class org.apache.wicket.Resource

getParameters, invalidate, isCacheable, onResourceRequested, setCacheable, setParameters

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicWebResource

public DynamicWebResource()

Creates a dynamic resource.

DynamicWebResource

public DynamicWebResource(String filename)

Creates a dynamic resource.

Parameters:

filename - The filename that will be set as the Content-Disposition header.

DynamicWebResource

public DynamicWebResource(Locale locale)

Creates a dynamic resource from for the given locale

Parameters:

locale - The locale of this resource

DynamicWebResource

public DynamicWebResource(Locale locale,
                          String filename)

Creates a dynamic resource from for the given locale

Parameters:

locale - The locale of this resource

filename - The filename that will be set as the Content-Disposition header.

Method Detail

setHeaders

protected void setHeaders(WebResponse response)

Description copied from class: WebResource

Subclasses can override this to set there headers when the resource is being served. By default 2 headers will be set if the Resource is cacheable

 response.setDateHeader("Expires", System.currentTimeMillis() + (3600 * 1000));
 response.setHeader("Cache-Control", "max-age=" + 3600);
 

So if a resource wants to control this or doesn't want to set this info it should override this method and don't call super.

Overrides:

setHeaders in class WebResource

Parameters:

response - The WebResponse where set(Date)Header can be called on.

See Also:

WebResource.setHeaders(org.apache.wicket.protocol.http.WebResponse)

getLocale

public Locale getLocale()

Returns the resource locale.

Returns:

The locale of this resource

getResourceStream

public IResourceStream getResourceStream()

Description copied from class: Resource

Returns a new IResourceStream that provides all data for the request. Despite its name, this method should return a new IResourceStream instance each time it is invoked (otherwise the InputStream returned from the IResourceStream would be at EOF when a second request is handled for the same Resource). The caller must invoke IResourceStream.close() when finished.

Specified by:

getResourceStream in class Resource

Returns:

Gets the resource to attach to the component.

getResourceState

protected abstract DynamicWebResource.ResourceState getResourceState()

Gets the byte array for our dynamic resource. If the subclass regenerates the data, it should set the lastModifiedTime too. This ensures that resource caching works correctly.

Returns:

The byte array for this dynamic resource.