public abstract class RenderedDynamicImageResource extends DynamicImageResource
The format of the image (and therefore the resource's extension) can be specified with setFormat(String). The default format is "PNG" because JPEG is lossy and makes generated images look bad and GIF has patent issues.
DefaultButtonImageResource
,
DefaultButtonImageResourceFactory
,
Serialized FormAbstractResource.ResourceResponse, AbstractResource.WriteCallback
IResource.Attributes
INTERNAL_HEADERS
Constructor and Description |
---|
RenderedDynamicImageResource(int width,
int height)
Constructor.
|
RenderedDynamicImageResource(int width,
int height,
String format)
Constructor.
|
Modifier and Type | Method and Description |
---|---|
int |
getHeight() |
protected byte[] |
getImageData(IResource.Attributes attributes)
Get image data for our dynamic image resource.
|
int |
getType() |
int |
getWidth() |
void |
invalidate()
Causes the image to be redrawn the next time its requested.
|
protected abstract boolean |
render(Graphics2D graphics,
IResource.Attributes attributes)
Override this method to provide your rendering code.
|
protected byte[] |
render(IResource.Attributes attributes)
Renders this image
|
void |
setHeight(int height) |
void |
setType(int type) |
void |
setWidth(int width) |
configureResponse, getFormat, newResourceResponse, setFormat, setLastModifiedTime, toImageData
configureCache, getCachingStrategy, respond, setResponseHeaders
public RenderedDynamicImageResource(int width, int height)
width
- Width of imageheight
- Height of imagepublic RenderedDynamicImageResource(int width, int height, String format)
width
- Width of imageheight
- Height of imageformat
- The format of the image (jpg, png or gif)public int getHeight()
public int getType()
public int getWidth()
public void invalidate()
public void setHeight(int height)
height
- The height to set.public void setType(int type)
type
- The type to set (one of BufferedImage.TYPE_*).public void setWidth(int width)
width
- The width to set.protected byte[] getImageData(IResource.Attributes attributes)
DynamicImageResource
DynamicImageResource.setLastModifiedTime(Time)
when it does so. This
ensures that image caching works correctly.getImageData
in class DynamicImageResource
attributes
- the context bringing the request, response and the parametersnull
means there is no image and 404
(Not found) response will be return.protected byte[] render(IResource.Attributes attributes)
attributes
- the current request attributesprotected abstract boolean render(Graphics2D graphics, IResource.Attributes attributes)
graphics
- The graphics context to render on.attributes
- the current request attributestrue
if the image was rendered. false
if the image size was changed
by the rendering implementation and the image should be re-rendered at the new size.Copyright © 2006–2014 Apache Software Foundation. All rights reserved.