javax.faces.component

Class UIImportConstants

java.lang.Object

javax.faces.component.UIComponent

javax.faces.component.UIComponentBase

javax.faces.component.UIImportConstants

All Implemented Interfaces:

EventListener, PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder

public class UIImportConstants
extends UIComponentBase

UIImportConstants imports a mapping of all constant field values of the given type in the current view.

The ViewDeclarationLanguage implementation must cause an instance of this component to be placed in the view for each occurrence of an <f:importConstants /> element placed inside of an <f:metadata /> element. The user must place <f:metadata /> as a direct child of the UIViewRoot. The ViewMetadata.createMetadataView(javax.faces.context.FacesContext) must take care of actual task of importing the constants.

Instances of this class participate in the regular Jakarta Server Faces lifecycle, including on Ajax requests.

The purpose of this component is to provide a mapping of all constant field values of the given type in the current view. Constant field values are all public static final fields of the given type. The map key represents the constant field name as String. The map value represents the actual constant field value. This works for classes, interfaces and enums.

Usage

The below constant fields:

 package com.example;
 
 public class Foo {
     public static final String FOO1 = "foo1";
     public static final String FOO2 = "foo2";
 }
 

 package com.example;
 
 public interface Bar {
     public static final String BAR1 = "bar1";
     public static final String BAR2 = "bar2";
 }
 

 package com.example;
 
 public enum Baz {
     BAZ1, BAZ2;
 }
 

Can be imported as below:

 <f:metadata>
     <f:importConstants type="com.example.Foo" />
     <f:importConstants type="com.example.Bar" var="Barrr" />
     <f:importConstants type="com.example.Baz" />
 </f:metadata>
 

And can be referenced as below:

 #{Foo.FOO1}, #{Foo.FOO2}, #{Barrr.BAR1}, #{Barrr.BAR2}, #{Baz.BAZ1}, #{Baz.BAZ2}
 

 <h:selectOneMenu value="#{bean.baz}" >
     <f:selectItems value="#{Baz}" />
 </h:selectOneMenu>
 

Since:

2.3

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPONENT_FAMILY The standard component family for this component.
static String	COMPONENT_TYPE The standard component type for this component.

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
UIImportConstants() Create a new UIImportConstants instance with renderer type set to null.

Method Summary

Modifier and Type	Method and Description
String	getFamily() Return the identifier of the component family to which this component belongs.
String	getType() Returns the fully qualified name of the type to import the constant field values for.
String	getVar() Returns name of request scope attribute under which constants will be exposed as a Map.
void	setType(String type) Sets the fully qualified name of the type to import the constant field values for.
void	setValueExpression(String name, javax.el.ValueExpression binding) Set the ValueExpression used to calculate the value for the specified attribute or property name, if any.
void	setVar(String var) Sets name of request scope attribute under which constants will be exposed as a Map.

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, getListenersForEventClass, getParent, getPassThroughAttributes, getRenderer, getRendererType, getRendersChildren, 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, visitTree

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 String COMPONENT_TYPE

The standard component type for this component.

See Also:

Constant Field Values

COMPONENT_FAMILY

public static final String COMPONENT_FAMILY

The standard component family for this component.

See Also:

Constant Field Values

Constructor Detail

UIImportConstants

public UIImportConstants()

Create a new UIImportConstants instance with renderer type set to null.

Method Detail

getFamily

public String getFamily()

Description copied from class: UIComponent

Return the identifier of the component family to which this component belongs. This identifier, in conjunction with the value of the rendererType property, may be used to select the appropriate Renderer for this component instance. Note this method should NOT return null

Specified by:

getFamily in class UIComponent

Returns:

the component family (not null).

getType

public String getType()

Returns the fully qualified name of the type to import the constant field values for.

Returns:

The fully qualified name of the type to import the constant field values for.

setType

public void setType(String type)

Sets the fully qualified name of the type to import the constant field values for.

Parameters:

type - The fully qualified name of the type to import the constant field values for.

getVar

public String getVar()

Returns name of request scope attribute under which constants will be exposed as a Map.

Returns:

Name of request scope attribute under which constants will be exposed as a Map.

setVar

public void setVar(String var)

Sets name of request scope attribute under which constants will be exposed as a Map.

Parameters:

var - Name of request scope attribute under which constants will be exposed as a Map.

setValueExpression

public void setValueExpression(String name,
                               javax.el.ValueExpression binding)

Set the ValueExpression used to calculate the value for the specified attribute or property name, if any. If a ValueExpression is set for the var property, throw an illegal argument exception.

Overrides:

setValueExpression in class UIComponent

Parameters:

name - Name of the attribute or property for which to set a ValueExpression

binding - The ValueExpression to set, or null to remove any currently set ValueExpression

Throws:

IllegalArgumentException - If name is one of id, parent, or var.

NullPointerException - If name is null.