org.omnifaces.component.output

Class Param<T>

java.lang.Object

javax.faces.component.UIComponent

javax.faces.component.UIComponentBase

javax.faces.component.UIParameter

org.omnifaces.component.output.Param<T>

Type Parameters:

T - The type of the value.

All Implemented Interfaces:

EventListener, PartialStateHolder, StateHolder, TransientStateHolder, ValueHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, ParamHolder<T>

public class Param<T>
extends UIParameter
implements ParamHolder<T>

The <o:param> is a component that extends the standard UIParameter to implement ValueHolder and thus support a Converter to convert the supplied value to string, if necessary.

You can use it the same way as <f:param>, you only need to change f: into o: to get the extra support for a Converter by usual means via the converter attribute of the tag, or the nested <f:converter> tag, or just automatically if a converter is already registered for the target class via @FacesConverter(forClass).

Also, if no value is specified, but children are present, then the encoded output of children will be returned as param value. This is useful when you want to supply JSF components or HTML as parameter of an unescaped <h:outputFormat>. For example,

 <h:outputFormat value="#{bundle.paragraph}" escape="false">
     <o:param><h:link outcome="contact" value="#{bundle.contact}" /></o:param>
 </h:outputFormat>
 

with this bundle

 paragraph = Please {0} for more information.
 contact = contact us
 

will result in the link being actually encoded as output format parameter value.

Since:

1.4

Author:

Bauke Scholtz

See Also:

ParamHolder

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPONENT_TYPE

Fields inherited from class javax.faces.component.UIParameter

COMPONENT_FAMILY

Fields inherited from class javax.faces.component.UIComponent

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

Constructor Summary

Constructors

Constructor and Description
Param()

Method Summary

Modifier and Type	Method and Description
void	encodeChildren(FacesContext context)
Converter<T>	getConverter() Returns the converter, if any.
T	getLocalValue() Returns the original, unconverted value of the parameter.
boolean	getRendersChildren()
String	getValue() Returns the value of the parameter as String.
void	setConverter(Converter converter)

Methods inherited from class javax.faces.component.UIParameter

getFamily, getName, isDisable, setDisable, setName, setValue

Methods inherited from class javax.faces.component.UIComponentBase

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

Methods inherited from class javax.faces.component.UIComponent

encodeAll, getClientId, getCompositeComponentParent, getContainerClientId, getCurrentComponent, getCurrentCompositeComponent, getNamingContainer, getPassThroughAttributes, getResourceBundleMap, getStateHelper, getStateHelper, getTransientStateHelper, getTransientStateHelper, getValueExpression, initialStateMarked, isCompositeComponent, isInView, isVisitable, popComponentFromEL, processEvent, pushComponentToEL, restoreTransientState, saveTransientState, setInView, setValueExpression, visitTree

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.omnifaces.component.ParamHolder

getName

Methods inherited from interface javax.faces.component.ValueHolder

setValue

Field Detail

COMPONENT_TYPE

public static final String COMPONENT_TYPE

See Also:

Constant Field Values

Constructor Detail

Param

public Param()

Method Detail

getConverter

public Converter<T> getConverter()

Description copied from interface: ParamHolder

Returns the converter, if any.

Specified by:

getConverter in interface ValueHolder

Specified by:

getConverter in interface ParamHolder<T>

Returns:

The converter, if any.

setConverter

public void setConverter(Converter converter)

Specified by:

setConverter in interface ValueHolder

getLocalValue

public T getLocalValue()

Description copied from interface: ParamHolder

Returns the original, unconverted value of the parameter.

Specified by:

getLocalValue in interface ValueHolder

Specified by:

getLocalValue in interface ParamHolder<T>

Returns:

The original, unconverted value of the parameter.

Throws:

ClassCastException - When actual value is not T.

getValue

public String getValue()

Description copied from interface: ParamHolder

Returns the value of the parameter as String. If the converter is set, or if any converter is available by Application.createConverter(Class), passing the value's class, then return the result of Converter.getAsString(javax.faces.context.FacesContext, javax.faces.component.UIComponent, Object), otherwise return the Object.toString() of the value.

Specified by:

getValue in interface ValueHolder

Specified by:

getValue in interface ParamHolder<T>

Overrides:

getValue in class UIParameter

Returns:

The value of the parameter as String.

See Also:

Converter.getAsString(javax.faces.context.FacesContext, javax.faces.component.UIComponent, Object)

getRendersChildren

public boolean getRendersChildren()

Overrides:

getRendersChildren in class UIComponentBase

encodeChildren

public void encodeChildren(FacesContext context)
                    throws IOException

Overrides:

encodeChildren in class UIComponentBase

Throws:

IOException