public abstract class Renderer
extends java.lang.Object
A Renderer converts the internal representation of
UIComponents into the output stream (or writer) associated with the response we are creating for a particular
request. Each Renderer knows how to render one or more UIComponent types (or classes), and
advertises a set of render-dependent attributes that it recognizes for each supported UIComponent.
Families of Renderers are packaged as a RenderKit, and together support the rendering of all of the
UIComponents in a view associated with a FacesContext. Within the set of Renderers for a
particular RenderKit, each must be uniquely identified by the rendererType property.
Individual Renderer instances will be instantiated as requested during the rendering process, and will remain
in existence for the remainder of the lifetime of a web application. Because each instance may be invoked from more
than one request processing thread simultaneously, they MUST be programmed in a thread-safe manner.
If the ListenerFor annotation is attached to the class definition of a
Renderer, that class must also implement ComponentSystemEventListener, and
the action pertaining to the processing of ResourceDependency on a Renderer described in
ListenerFor must be taken.
If the ResourceDependency annotation is attached to the class definition of a
Renderer, the action pertaining to the processing of ResourceDependency on a
Renderer described in UIComponent.getChildren() must be taken.
| Modifier and Type | Field and Description |
|---|---|
static java.lang.String |
PASSTHROUGH_RENDERER_LOCALNAME_KEY
The key in the component passthrough attributes |
| Constructor and Description |
|---|
Renderer() |
| Modifier and Type | Method and Description |
|---|---|
java.lang.String |
convertClientId(FacesContext context,
java.lang.String clientId)
Convert the component generated client id to a form suitable for transmission to the client.
|
void |
decode(FacesContext context,
UIComponent component)
Decode any new state of the specified
UIComponent from the request contained in the specified
FacesContext, and store that state on the UIComponent. |
void |
encodeBegin(FacesContext context,
UIComponent component)
Render the beginning specified
UIComponent to the output stream or writer associated with the response we are
creating. |
void |
encodeChildren(FacesContext context,
UIComponent component)
Render the child components of this
UIComponent, following the rules described for encodeBegin()
to acquire the appropriate value to be rendered. |
void |
encodeEnd(FacesContext context,
UIComponent component)
Render the ending of the current state of the specified
UIComponent, following the rules described for
encodeBegin() to acquire the appropriate value to be rendered. |
java.lang.Object |
getConvertedValue(FacesContext context,
UIComponent component,
java.lang.Object submittedValue)
Attempt to convert previously stored state information into an object of the type required for this component
(optionally using the registered
Converter for this component, if there is one). |
boolean |
getRendersChildren()
Return a flag indicating whether this
Renderer is responsible for rendering the children the component it is
asked to render. |
public static final java.lang.String PASSTHROUGH_RENDERER_LOCALNAME_KEY
The key in the component passthrough attributes Map for the localName of the element corresponding to the
component.
public void decode(FacesContext context, UIComponent component)
Decode any new state of the specified UIComponent from the request contained in the specified
FacesContext, and store that state on the UIComponent.
During decoding, events may be enqueued for later processing (by event listeners that have registered an interest),
by calling queueEvent() on the associated UIComponent.
context - FacesContext for the request we are processingcomponent - UIComponent to be decoded.java.lang.NullPointerException - if context or component is nullpublic void encodeBegin(FacesContext context, UIComponent component) throws java.io.IOException
Render the beginning specified UIComponent to the output stream or writer associated with the response we are
creating. If the conversion attempted in a previous call to getConvertedValue() for this component
failed, the state information saved during execution of decode() should be used to reproduce the
incorrect input.
context - FacesContext for the request we are processingcomponent - UIComponent to be renderedjava.io.IOException - if an input/output error occurs while renderingjava.lang.NullPointerException - if context or component is nullpublic void encodeChildren(FacesContext context, UIComponent component) throws java.io.IOException
Render the child components of this UIComponent, following the rules described for encodeBegin()
to acquire the appropriate value to be rendered. This method will only be called if the rendersChildren
property of this component is true.
context - FacesContext for the response we are creatingcomponent - UIComponent whose children are to be renderedjava.io.IOException - if an input/output error occurs while renderingjava.lang.NullPointerException - if context or component is nullpublic void encodeEnd(FacesContext context, UIComponent component) throws java.io.IOException
Render the ending of the current state of the specified UIComponent, following the rules described for
encodeBegin() to acquire the appropriate value to be rendered.
context - FacesContext for the response we are creatingcomponent - UIComponent to be renderedjava.io.IOException - if an input/output error occurs while renderingjava.lang.NullPointerException - if context or component is nullpublic java.lang.String convertClientId(FacesContext context, java.lang.String clientId)
Convert the component generated client id to a form suitable for transmission to the client.
The default implementation returns the argument clientId unchanged.
context - FacesContext for the current requestclientId - the client identifier to be converted to client a specific format.clientIdjava.lang.NullPointerException - if context or clientId is nullpublic boolean getRendersChildren()
Return a flag indicating whether this Renderer is responsible for rendering the children the component it is
asked to render. The default implementation returns false.
public java.lang.Object getConvertedValue(FacesContext context, UIComponent component, java.lang.Object submittedValue) throws ConverterException
Attempt to convert previously stored state information into an object of the type required for this component
(optionally using the registered Converter for this component, if there is one). If
conversion is successful, the new value should be returned from this method; if not, a ConverterException
should be thrown.
context - FacesContext for the request we are processingcomponent - UIComponent to be decoded.submittedValue - a value stored on the component during decode.ConverterException - if the submitted value cannot be converted successfully.java.lang.NullPointerException - if context or component is null