org.apache.myfaces.custom.buffer
Class AbstractBuffer

java.lang.Object
  javax.faces.component.UIComponent
      javax.faces.component.UIComponentBase
          org.apache.myfaces.custom.buffer.AbstractBuffer

All Implemented Interfaces:

java.util.EventListener, javax.faces.component.PartialStateHolder, javax.faces.component.StateHolder, javax.faces.event.ComponentSystemEventListener, javax.faces.event.FacesListener, javax.faces.event.SystemEventListenerHolder

Direct Known Subclasses:

Buffer

@JSFComponent(name="t:buffer",
              clazz="org.apache.myfaces.custom.buffer.Buffer",
              tagClass="org.apache.myfaces.custom.buffer.BufferTag")
@JSFJspProperties(properties={@JSFJspProperty(name="rendered",returnType="boolean",tagExcluded=true),@JSFJspProperty(name="binding",returnType="java.lang.String",tagExcluded=true),@JSFJspProperty(name="id",returnType="java.lang.String",tagExcluded=true)})
public abstract class AbstractBuffer
extends javax.faces.component.UIComponentBase

A component that renders its child components into an in-memory buffer rather than render them directly to the response stream.

Property "into" is an EL expression that specifies where to store a String holding the results of rendering all the children of this component; this is assigned to after rendering of this component (and its children) is complete.

Typically, an h:output tag is then used later in the same page to output the buffer contents.

This can be useful with JSF1.1/JSP2.0 to work around the well-known problem where on first render of a page, a component "A" cannot reference a component "B" which is defined later in the page because it has not yet been created. A solution is to define "B" before "A", but wrapped in a Buffer component. Component A can then be rendered and successfully reference "B" because it now exists. And later in the page, the buffer contents can then be output, preserving the original layout.

This can also be useful when rendering the same data block multiple times within a page. For example, a datatable can be rendered with a datascroller both before and after it; first render the table into a buffer B1, then render the datascroller into a buffer B2, then output buffers B2,B1,B2.

Since:

1.1.7

Version:

$Revision: 691871 $ $Date: 2008-09-03 23:32:08 -0500 (Wed, 03 Sep 2008) $

Author:

Sylvain Vieujot (latest modification by $Author: lu4242 $)

Field Summary

static java.lang.String	COMPONENT_FAMILY
static java.lang.String	COMPONENT_TYPE

Fields inherited from class javax.faces.component.UIComponent

BEANINFO_KEY, bindings, COMPOSITE_COMPONENT_TYPE_KEY, COMPOSITE_FACET_NAME, CURRENT_COMPONENT, CURRENT_COMPOSITE_COMPONENT, FACETS_KEY, VIEW_LOCATION_KEY

Constructor Summary

AbstractBuffer()

Method Summary

protected abstract java.lang.String	getInto() An EL expression that specifies where to store a String holding the results of rendering all the children of this component; this is assigned to after rendering of this component (and its children) is complete.
protected abstract java.lang.String	getLocalInto()
abstract void	setInto(java.lang.String into)

Methods inherited from class javax.faces.component.UIComponentBase

addClientBehavior, addFacesListener, broadcast, clearInitialState, decode, encodeBegin, encodeChildren, encodeEnd, findComponent, getAttributes, getChildCount, getChildren, getClientBehaviors, getClientId, getDefaultEventName, getEventNames, getFacesContext, getFacesListeners, getFacet, getFacetCount, getFacets, getFacetsAndChildren, getId, getParent, getRenderer, getRendererType, getRendersChildren, getValueBinding, initialStateMarked, invokeOnComponent, isRendered, isTransient, markInitialState, processDecodes, processRestoreState, processSaveState, processUpdates, processValidators, queueEvent, removeFacesListener, restoreAttachedState, restoreState, saveAttachedState, saveState, setId, setParent, setRendered, setRendererType, setTransient, setValueBinding, visitTree

Methods inherited from class javax.faces.component.UIComponent

encodeAll, getClientId, getCompositeComponentParent, getContainerClientId, getCurrentComponent, getCurrentCompositeComponent, getFamily, getListenersForEventClass, getNamingContainer, getResourceBundleMap, getStateHelper, getStateHelper, getValueExpression, isCompositeComponent, isInView, isVisitable, popComponentFromEL, processEvent, pushComponentToEL, setInView, setValueExpression, subscribeToEvent, unsubscribeFromEvent

Methods inherited from class java.lang.Object

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

Field Detail

COMPONENT_TYPE

public static final java.lang.String COMPONENT_TYPE

See Also:

Constant Field Values

COMPONENT_FAMILY

public static final java.lang.String COMPONENT_FAMILY

See Also:

Constant Field Values

Constructor Detail

AbstractBuffer

public AbstractBuffer()

Method Detail

getLocalInto

protected abstract java.lang.String getLocalInto()

setInto

public abstract void setInto(java.lang.String into)

getInto

@JSFProperty(required=true,
             localMethod=true)
protected abstract java.lang.String getInto()

An EL expression that specifies where to store a String holding the results of rendering all the children of this component; this is assigned to after rendering of this component (and its children) is complete.