public abstract class UIComponent extends Object implements PartialStateHolder, TransientStateHolder, SystemEventListenerHolder, ComponentSystemEventListener
 UIComponent is the base class for all user interface components in Jakarta Server
 Faces. The set of UIComponent instances associated with a particular request and response are organized into
 a component tree under a UIViewRoot that represents the entire content of the request or response.
 
 For the convenience of component developers, UIComponentBase provides the default behavior that is specified
 for a UIComponent, and is the base class for all of the concrete UIComponent "base" implementations.
 Component writers are encouraged to subclass UIComponentBase, instead of directly implementing this abstract
 class, to reduce the impact of any future changes to the method signatures.
 
 If the ListenerFor annotation is attached to the class definition of a
 Component, that class must also implement ComponentSystemEventListener.
 
Dynamically modifying the component tree can happen at any time, during and after restoring the view, but not during state saving and needs to function properly with respect to rendering and state saving
| Modifier and Type | Field and Description | 
|---|---|
| static String | ATTRS_WITH_DECLARED_DEFAULT_VALUESThis constant enables one to quickly discover the names of the declared composite component attributes that have been given default values by the composite component author. | 
| static String | BEANINFO_KEY
 The value of this constant is used as the key in the component attribute map, the value for which is a
  | 
| protected Map<String,ValueExpression> | bindingsDeprecated.  | 
| static String | COMPOSITE_COMPONENT_TYPE_KEY
 The value of this constant is used as the key in the composite component BeanDescriptor for a
  | 
| static String | COMPOSITE_FACET_NAME
 The value of this constant is used as the key in the  | 
| static String | CURRENT_COMPONENTDeprecated.   | 
| static String | CURRENT_COMPOSITE_COMPONENTDeprecated.   | 
| static String | FACETS_KEY
 The value of this constant is used as the key in the composite component BeanDescriptor for the
  | 
| static String | HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME
 The  | 
| static String | VIEW_LOCATION_KEY
 The value of this constant is used as the key in the component attributes  | 
| Constructor and Description | 
|---|
| UIComponent() | 
| Modifier and Type | Method and Description | 
|---|---|
| protected abstract void | addFacesListener(FacesListener listener)
 Add the specified  FacesListenerto the set of listeners registered to receive event notifications from thisUIComponent. | 
| abstract void | broadcast(FacesEvent event)
 Broadcast the specified  FacesEventto all registered event listeners who have expressed an interest in events
 of this type. | 
| void | clearInitialState()
 An implementation of  | 
| abstract void | decode(FacesContext context)
 Decode any new state of this  UIComponentfrom the request contained in the specifiedFacesContext,
 and store this state as needed. | 
| void | encodeAll(FacesContext context)
 If this component returns  truefromisRendered(), take the following action. | 
| abstract void | encodeBegin(FacesContext context)
 If our  renderedproperty istrue, render the
 beginning of the current state of thisUIComponentto the response contained in the specifiedFacesContext. | 
| abstract void | encodeChildren(FacesContext context) | 
| abstract void | encodeEnd(FacesContext context) | 
| abstract UIComponent | findComponent(String expr)
 Search for and return the  UIComponentwith anidthat
 matches the specified search expression (if any), according to the algorithm described below. | 
| abstract Map<String,Object> | getAttributes()
 Return a mutable  Maprepresenting the attributes (and properties, see below) associated wth thisUIComponent, keyed by attribute name (which must be a String). | 
| abstract int | getChildCount()
 Return the number of child  UIComponents that are associated with thisUIComponent. | 
| abstract List<UIComponent> | getChildren() | 
| String | getClientId()
 Enable Jakarta Expression Language to access the  | 
| abstract String | getClientId(FacesContext context)
 Return a client-side identifier for this component, generating one if necessary. | 
| static UIComponent | getCompositeComponentParent(UIComponent component)
 Finds the nearest composite component parent of the specified component. | 
| String | getContainerClientId(FacesContext context)
 Allow components that implement  NamingContainerto selectively disable prepending their clientId to their
 descendent's clientIds by breaking the prepending logic into a separately callable method. | 
| static UIComponent | getCurrentComponent(FacesContext context)
 Return the  | 
| static UIComponent | getCurrentCompositeComponent(FacesContext context)
 Return the closest ancestor component, relative to the component returned from  | 
| protected abstract FacesContext | getFacesContext()
 Convenience method to return the  FacesContextinstance for the current request. | 
| protected abstract FacesListener[] | getFacesListeners(Class clazz)
 Return an array of registered  FacesListeners that are instances of the specified class. | 
| abstract UIComponent | getFacet(String name)
 Convenience method to return the named facet, if it exists, or  nullotherwise. | 
| int | getFacetCount()
 Return the number of facet  UIComponents that are associated with thisUIComponent. | 
| abstract Map<String,UIComponent> | getFacets()
 Return a mutable  Maprepresenting the facetUIComponents associated with thisUIComponent, keyed by facet name (which must be a String). | 
| abstract Iterator<UIComponent> | getFacetsAndChildren() | 
| abstract String | getFamily()Return the identifier of the component family to which this component belongs. | 
| abstract String | getId()
 Return the component identifier of this  UIComponent. | 
| List<SystemEventListener> | getListenersForEventClass(Class<? extends SystemEvent> eventClass)
 This implementation throws  | 
| UIComponent | getNamingContainer()
 Starting with "this", return the closest component in the ancestry that is a  | 
| abstract UIComponent | getParent()
 Return the parent  UIComponentof thisUIComponent, if any. | 
| Map<String,Object> | getPassThroughAttributes()
 This is a convenience method that simply calls  | 
| Map<String,Object> | getPassThroughAttributes(boolean create)
 This method has the same specification as  | 
| protected abstract Renderer | getRenderer(FacesContext context)
 Convenience method to return the  Rendererinstance associated with this component, if any; otherwise, returnnull. | 
| abstract String | getRendererType()
 Return the  Renderertype for thisUIComponent(if any). | 
| abstract boolean | getRendersChildren()
 Return a flag indicating whether this component is responsible for rendering its child components. | 
| Map<String,String> | getResourceBundleMap()
 Return a  | 
| protected StateHelper | getStateHelper()
 Return the  | 
| protected StateHelper | getStateHelper(boolean create)
 Like  | 
| TransientStateHelper | getTransientStateHelper()
 Return the  | 
| TransientStateHelper | getTransientStateHelper(boolean create)
 Return the  | 
| abstract ValueBinding | getValueBinding(String name)Deprecated. 
 This has been replaced by  getValueExpression(java.lang.String). | 
| ValueExpression | getValueExpression(String name)
 Return the  ValueExpressionused to calculate the value for the specified attribute or property name, if any. | 
| boolean | initialStateMarked()
 An implementation of  | 
| boolean | invokeOnComponent(FacesContext context,
                 String clientId,
                 ContextCallback callback)
 Starting at this component in the View hierarchy, search for a component
 with a  clientIdequal to the argumentclientIdand, if found, call theContextCallback.invokeContextCallback(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent)method on the argumentcallback, passing the currentFacesContextand the found component as arguments. | 
| static boolean | isCompositeComponent(UIComponent component)
 Return  | 
| boolean | isInView()
 Return  | 
| abstract boolean | isRendered()
 Return  trueif this component (and its children) should be rendered during the Render Response
 phase of the request processing lifecycle. | 
| protected boolean | isVisitable(VisitContext context)
 Return  | 
| void | markInitialState()
 An implementation of  | 
| void | popComponentFromEL(FacesContext context)
 Pop the current  | 
| abstract void | processDecodes(FacesContext context)
 Perform the component tree processing required by the Apply Request
 Values phase of the request processing lifecycle for all facets of this component, all children of this
 component, and this component itself, as follows. | 
| void | processEvent(ComponentSystemEvent event)The default implementation performs the following action. | 
| abstract void | processRestoreState(FacesContext context,
                   Object state)
 Perform the component tree processing required by the Restore View
 phase of the request processing lifecycle for all facets of this component, all children of this component, and this
 component itself, as follows. | 
| abstract Object | processSaveState(FacesContext context)
 Perform the component tree processing required by the state saving portion
 of the Render Response phase of the request processing lifecycle for all facets of this component, all
 children of this component, and this component itself, as follows. | 
| abstract void | processUpdates(FacesContext context)
 Perform the component tree processing required by the Update Model
 Values phase of the request processing lifecycle for all facets of this component, all children of this
 component, and this component itself, as follows. | 
| abstract void | processValidators(FacesContext context)
 Perform the component tree processing required by the Process
 Validations phase of the request processing lifecycle for all facets of this component, all children of this
 component, and this component itself, as follows. | 
| void | pushComponentToEL(FacesContext context,
                 UIComponent component)
 Push the current  | 
| abstract void | queueEvent(FacesEvent event)
 Queue an event for broadcast at the end of the current request processing lifecycle phase. | 
| protected abstract void | removeFacesListener(FacesListener listener)
 Remove the specified  FacesListenerfrom the set of listeners registered to receive event notifications from
 thisUIComponent. | 
| void | restoreTransientState(FacesContext context,
                     Object state)
 For components that need to support the concept of transient state, this method will restore any state saved on a
 prior call to  | 
| Object | saveTransientState(FacesContext context)For components that need to support the concept of transient state, this method will save any state that is known to be transient in nature. | 
| abstract void | setId(String id)
 Set the component identifier of this  UIComponent(if any). | 
| void | setInView(boolean isInView)Updates the status as to whether or not this component is currently within the view hierarchy. | 
| abstract void | setParent(UIComponent parent)
 Set the parent  | 
| abstract void | setRendered(boolean rendered)
 Set the  renderedproperty of thisUIComponent. | 
| abstract void | setRendererType(String rendererType) | 
| abstract void | setValueBinding(String name,
               ValueBinding binding)Deprecated. 
 This has been replaced by  setValueExpression(java.lang.String, jakarta.el.ValueExpression). | 
| void | setValueExpression(String name,
                  ValueExpression binding)
 Set the  ValueExpressionused to calculate the value for the specified attribute or property name, if any. | 
| void | subscribeToEvent(Class<? extends SystemEvent> eventClass,
                ComponentSystemEventListener componentListener)
 This implementation throws  | 
| void | unsubscribeFromEvent(Class<? extends SystemEvent> eventClass,
                    ComponentSystemEventListener componentListener)
 This implementation throws  | 
| boolean | visitTree(VisitContext visitContext,
         VisitCallback callback)Perform a tree visit starting at this node in the tree. | 
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitisTransient, restoreState, saveState, setTransientpublic static final String HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME
 The ServletContext init parameter consulted by the UIComponent to tell whether or not the
 CURRENT_COMPONENT and CURRENT_COMPOSITE_COMPONENT attribute keys should be honored as specified.
 
 If this parameter is not specified, or is set to false, the contract specified by the CURRENT_COMPONENT and
 CURRENT_COMPOSITE_COMPONENT method is not honored. If this parameter is set to true, the contract is
 honored.
 
public static final String BEANINFO_KEY
 The value of this constant is used as the key in the component attribute map, the value for which is a
 java.beans.BeanInfo implementation describing the composite component. This BeanInfo is
 known as the composite component BeanInfo.
 
public static final String FACETS_KEY
 The value of this constant is used as the key in the composite component BeanDescriptor for the
 Map<PropertyDescriptor> that contains meta-information for the declared facets for this composite
 component. This map must contain an entry under the key COMPOSITE_FACET_NAME, even if no facets were
 explicitly declared. See COMPOSITE_FACET_NAME.
 
public static final String VIEW_LOCATION_KEY
 The value of this constant is used as the key in the component attributes Map for the
 Location in the view at which this component instance resides.
 
public static final String COMPOSITE_COMPONENT_TYPE_KEY
 The value of this constant is used as the key in the composite component BeanDescriptor for a
 ValueExpression that evaluates to the component-type of the composite component
 root UIComponent for this composite component, if one was declared by the composite component
 author.
 
public static final String COMPOSITE_FACET_NAME
 The value of this constant is used as the key in the Map returned as described in FACETS_KEY
 for the PropertyDescriptor describing the composite component facet. The value of this constant is also
 used as the key in the Map returned from getFacets(). In this case, it refers to the actual facet
 that is the UIPanel that is the parent of the all of the components in the
 <composite:implementation> section of the composite component VDL file.
 
public static final String ATTRS_WITH_DECLARED_DEFAULT_VALUES
 This constant enables one to quickly discover the names of the declared composite component attributes that have been
 given default values by the composite component author. The information is exposed as a
 Collection<String> returned from the getValue() method on the composite component
 BeanDescriptor, when this constant is passed as the argument.
 
@Deprecated public static final String CURRENT_COMPONENT
 The key to which the UIComponent currently being processed will
 be associated with within the FacesContext attributes map. The use of this
 constant is deprecated. Please see HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME to enable its use.
 
FacesContext.getAttributes(), 
Constant Field Values@Deprecated public static final String CURRENT_COMPOSITE_COMPONENT
 The key to which the composite UIComponent currently
 being processed will be associated with within the FacesContext attributes map.
 The use of this constant is deprecated. Please see
 HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME to enable its use.
 
FacesContext.getAttributes(), 
Constant Field Values@Deprecated protected Map<String,ValueExpression> bindings
public abstract Map<String,Object> getAttributes()
 Return a mutable Map representing the attributes (and properties, see below) associated wth this
 UIComponent, keyed by attribute name (which must be a String). The returned implementation must support all
 of the standard and optional Map methods, plus support the following additional requirements:
 
Map implementation must implement the java.io.Serializable interface.null key or value must throw a NullPointerException.ClassCastException.UIComponent's implementation class,
 the following methods will have special behavior:
 containsKey - Return false.get() - If the property is readable, call the getter method and return the returned value (wrapping
 primitive values in their corresponding wrapper classes); otherwise throw IllegalArgumentException.put() - If the property is writeable, call the setter method to set the corresponding value
 (unwrapping primitive values in their corresponding wrapper classes). If the property is not writeable, or an attempt
 is made to set a property of primitive type to null, throw IllegalArgumentException.remove - Throw IllegalArgumentException.public Map<String,Object> getPassThroughAttributes()
 This is a convenience method that simply calls getPassThroughAttributes(boolean), passing true as
 the argument. This method must never return null.
 
public Map<String,Object> getPassThroughAttributes(boolean create)
 This method has the same specification as getPassThroughAttributes() except that it is allowed to return
 null if and only if the argument create is false and no pass through attribute data structure
 exists for this instance. The returned Map implementation must support all of the standard and optional
 Map methods, plus support the following additional requirements. The map must be stored in using
 getStateHelper().
 
 The Map implementation must implement java.io.Serializable.
 
 Any attempt to add a null key or value must throw a NullPointerException.
 
 Any attempt to add a key that is not a String must throw an IllegalArgumentException.
 
For backward compatibility with components that extend directly from this class, a default implementation is provided that returns the empty map.
create - if true, a new Map instance will be created if it does not exist already. If
 false, and there is no existing Map instance, one will not be created and null
 will be returned.Map instance, or null.public ValueExpression getValueExpression(String name)
 Return the ValueExpression used to calculate the value for the specified attribute or property name, if any.
 
This method must be overridden and implemented for components that comply with Jakarta Server Faces 1.2 and later.
name - Name of the attribute or property for which to retrieve a ValueExpressionnull.NullPointerException - if name is nullpublic void setValueExpression(String name, ValueExpression binding)
 Set the ValueExpression used to calculate the value for the specified attribute or property name, if any.
 
 The implementation must call Expression.isLiteralText() on the argument expression. If
 isLiteralText() returns true, invoke ValueExpression.getValue(jakarta.el.ELContext) on the argument
 expression and pass the result as the value parameter in a call to this. where getAttributes().put(name, value)name is the argument name. If an exception
 is thrown as a result of calling ValueExpression.getValue(jakarta.el.ELContext), wrap it in a FacesException
 and re-throw it. If isLiteralText() returns false, simply store the un-evaluated
 expression argument in the collection of ValueExpressions under the key given by the
 argument name.
 
This method must be overridden and implemented for components that comply with Jakarta Server Faces 1.2 and later.
name - Name of the attribute or property for which to set a ValueExpressionbinding - The ValueExpression to set, or null to remove any currently set
 ValueExpressionIllegalArgumentException - if name is one of id or parentNullPointerException - if name is nullpublic void markInitialState()
 An implementation of PartialStateHolder.markInitialState(), this method is called by the runtime to indicate
 that the instance should start tracking changes to its state.
 
markInitialState in interface PartialStateHolderpublic boolean initialStateMarked()
 An implementation of PartialStateHolder.initialStateMarked(), this method is called by the runtime to test if
 the PartialStateHolder.markInitialState() method was called.
 
initialStateMarked in interface PartialStateHoldertrue if the initial state is marked, false otherwise.public void clearInitialState()
 An implementation of PartialStateHolder.clearInitialState(), this method is called by the runtime to tell the
 instance to stop tracking state changes.
 
clearInitialState in interface PartialStateHolderprotected StateHelper getStateHelper()
 Return the StateHelper instance used to help this component implement PartialStateHolder.
 
protected StateHelper getStateHelper(boolean create)
 Like getStateHelper(), but only create a state helper instance if the argument creat is
 true.
 
create - if true, a new StateHelper instance will be created if it does not exist already.
 If false, and there is no existing StateHelper instance, one will not be created and
 null will be returned.public TransientStateHelper getTransientStateHelper()
 Return the TransientStateHelper instance for this UIComponent instance. The default
 implementation simply calls through to getTransientStateHelper(boolean) passing true as the
 argument.
 
public TransientStateHelper getTransientStateHelper(boolean create)
 Return the TransientStateHelper instance for this UIComponent instance.
 
create - if true create, if necessary, any internal data structures. If false, do not
 create any instances. In this case, it is possible for this method to return null.public void restoreTransientState(FacesContext context, Object state)
 For components that need to support the concept of transient state, this method will restore any state saved on a
 prior call to saveTransientState(jakarta.faces.context.FacesContext).
 
restoreTransientState in interface TransientStateHoldercontext - the Faces contextstate - the object containing transient valuespublic Object saveTransientState(FacesContext context)
For components that need to support the concept of transient state, this method will save any state that is known to be transient in nature.
saveTransientState in interface TransientStateHoldercontext - the Faces context.public boolean isInView()
 Return true if this component is within the view hierarchy otherwise false
true if within a view hierarchy, false otherwise.public void setInView(boolean isInView)
 Updates the status as to whether or not this component is currently within the view hierarchy. This method
 must never be called by developers; a UIComponent's internal implementation will call it as components are
 added to or removed from a parent's child List or facet Map.
 
isInView - flag indicating whether or not this component is within the view hierachypublic String getClientId()
 Enable Jakarta Expression Language to access the clientId of a component. This is particularly useful in
 combination with the component and cc implicit objects. A default implementation is
 provided that simply calls FacesContext.getCurrentInstance() and then calls through to
 getClientId(FacesContext).
 
public abstract String getClientId(FacesContext context)
 Return a client-side identifier for this component, generating one if necessary. The associated Renderer, if
 any, will be asked to convert the clientId to a form suitable for transmission to the client.
 
 The return from this method must be the same value throughout the lifetime of the instance, unless the
 id property of the component is changed, or the component is placed in a NamingContainer whose
 client ID changes (for example, UIData). However, even in these cases, consecutive calls to this method must
 always return the same value. The implementation must follow these steps in determining the clientId:
 
 Find the closest ancestor to this component in the view hierarchy that implements
 NamingContainer. Call getContainerClientId() on it and save the result as the
 parentId local variable. Call getId() on this component and save the result as the
 myId local variable. If myId is null, call
 context.getViewRoot().createUniqueId() and assign the result to myId. If parentId is
 non-null, let myId equal parentId
 + . Call UINamingContainer.getSeparatorChar(jakarta.faces.context.FacesContext) + myIdRenderer.convertClientId(jakarta.faces.context.FacesContext, java.lang.String), passing
 myId, and return the result.
 
context - The FacesContext for the current requestNullPointerException - if context is nullpublic String getContainerClientId(FacesContext context)
 Allow components that implement NamingContainer to selectively disable prepending their clientId to their
 descendent's clientIds by breaking the prepending logic into a separately callable method. See getClientId()
 for usage.
 
 By default, this method will call through to getClientId() and return the result.
context - the Faces context.NullPointerException - if context is nullpublic abstract String getFamily()
 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
 
public abstract String getId()
 Return the component identifier of this UIComponent.
 
public abstract void setId(String id)
 Set the component identifier of this UIComponent (if any). Component identifiers must obey the following
 syntax restrictions:
 
 Component identifiers must also obey the following semantic restrictions (note that this restriction is
 NOT enforced by the setId() implementation):
 
UIComponent that is a NamingContainer, or within the scope of the entire component
 tree if there is no such ancestor that is a NamingContainer.id - The new component identifier, or null to indicate that this UIComponent does not have
 a component identifierIllegalArgumentException - if id is not syntactically validpublic abstract UIComponent getParent()
 Return the parent UIComponent of this UIComponent, if any. A component must allow child
 components to be added to and removed from the list of children of this component, even though the child component
 returns null from getParent( ).
 
public abstract void setParent(UIComponent parent)
 Set the parent UIComponent of this
 UIComponent. If
 parent.isInView() returns true, calling this method will first cause a
 PreRemoveFromViewEvent to be published, for this node, and then the children of this
 node. Then, once the re-parenting has occurred, a PostAddToViewEvent will be published as
 well, first for this node, and then for the node's children, but only if any
 of the following conditions are true.
 
 FacesContext.getCurrentPhaseId() returns PhaseId.RESTORE_VIEW
 and partial state saving is enabled.
 
 FacesContext.isPostback() returns false and
 FacesContext.getCurrentPhaseId() returns something other than
 PhaseId.RESTORE_VIEW
 
 This method must never be called by developers; a UIComponent's internal implementation will call it
 as components are added to or removed from a parent's child List or facet Map.
 
parent - The new parent, or null for the root node of a component treepublic abstract boolean isRendered()
 Return true if this component (and its children) should be rendered during the Render Response
 phase of the request processing lifecycle.
 
true if the component should be rendered, false otherwise.public abstract void setRendered(boolean rendered)
 Set the rendered property of this UIComponent.
 
rendered - If true render this component; otherwise, do not render this componentpublic abstract String getRendererType()
 Return the Renderer type for this UIComponent (if any).
 
public abstract void setRendererType(String rendererType)
 Set the Renderer type for this UIComponent, or null for components that render
 themselves.
 
rendererType - Logical identifier of the type of Renderer to use, or null for components
 that render themselvespublic abstract boolean getRendersChildren()
 Return a flag indicating whether this component is responsible for rendering its child components. The default
 implementation in UIComponentBase.getRendersChildren() tries to find the renderer for this component. If it
 does, it calls Renderer.getRendersChildren() and returns the result. If it doesn't, it returns false. As of
 version 1.2 of the Jakarta Server Faces Specification, component authors are encouraged to return true
 from this method and rely on UIComponentBase.encodeChildren(jakarta.faces.context.FacesContext).
 
true if the component renders its children, false otherwise.public Map<String,String> getResourceBundleMap()
 Return a Map<String,String> of the ResourceBundle for this component. A component may
 have a ResourceBundle associated with it. This bundle may contain localized properties relating to
 instances of this component. The default implementation first looks for a ResourceBundle with a base
 name equal to the fully qualified class name of the current UIComponent this and Locale
 equal to the Locale of the current UIViewRoot. If no such bundle is found, and the
 component is a composite component, let resourceName be the resourceName of the Resource
 for this composite component, replacing the file extension with ".properties". Let libraryName be the
 libraryName of the the Resource for this composite component. Call
 ResourceHandler.createResource(java.lang.String,java.lang.String), passing the
 derived resourceName and libraryName. Note that this will automatically allow for the localization
 of the ResourceBundle due to the localization facility implemented in createResource, which
 is specified in section 2.6.1.3 of the spec prose document. If the resultant Resource exists and can be
 found, the InputStream for the resource is used to create a ResourceBundle. If either of
 the two previous steps for obtaining the ResourceBundle for this component is successful, the
 ResourceBundle is wrapped in a Map<String,String> and returned. Otherwise
 Collections.EMPTY_MAP is returned.
 
public abstract List<UIComponent> getChildren()
 Return a mutable List representing the child
 UIComponents associated with this component. The returned implementation must support all of the standard and
 optional List methods, plus support the following additional requirements:
 
List implementation must implement the java.io.Serializable interface.null must throw a NullPointerExceptionUIComponent must throw a ClassCastException.parent property of the child must be set to this
 component instance. If the parent property of the child was already non-null, the child must first be
 removed from its previous parent (where it may have been either a child or a facet).parent property of the child must be set to
 null.
 After the child component has been added to the view, Application.publishEvent(jakarta.faces.context.FacesContext, java.lang.Class<? extends jakarta.faces.event.SystemEvent>, java.lang.Object) must
 be called, passing PostAddToViewEvent.class as the first argument and the
 newly added component as the second argument if any the following cases are true.
 
 FacesContext.getCurrentPhaseId() returns PhaseId.RESTORE_VIEW
 and partial state saving is enabled.
 
 FacesContext.isPostback() returns false and
 FacesContext.getCurrentPhaseId() returns something other than
 PhaseId.RESTORE_VIEW
 
public abstract int getChildCount()
 Return the number of child UIComponents that are associated with this UIComponent. If there are no
 children, this method must return 0. The method must not cause the creation of a child component list.
 
public abstract UIComponent findComponent(String expr)
 Search for and return the UIComponent with an id that
 matches the specified search expression (if any), according to the algorithm described below.
 
 WARNING: The found UIComponent instance, if any, is returned without regard for its
 tree traversal context. Retrieving an Jakarta Expression Language-bound attribute from the component is not safe.
 Jakarta Expression Language expressions can contain implicit objects, such as #{component}, which assume
 they are being evaluated within the scope of a tree traversal context. Evaluating expressions with these kinds of
 implicit objects outside of a tree traversal context produces undefined results. See invokeOnComponent(jakarta.faces.context.FacesContext, java.lang.String, jakarta.faces.component.ContextCallback) for a
 method that does correctly account for the tree traversal context when operating on the found
 UIComponent instance. invokeOnComponent(jakarta.faces.context.FacesContext, java.lang.String, jakarta.faces.component.ContextCallback) is also useful to find components given a simple
 clientId.
 
 Component identifiers are required to be unique within the scope of the closest ancestor NamingContainer that
 encloses this component (which might be this component itself). If there are no NamingContainer components in
 the ancestry of this component, the root component in the tree is treated as if it were a NamingContainer,
 whether or not its class actually implements the NamingContainer interface.
 
 A search expression consists of either an identifier (which is matched exactly against the id
 property of a UIComponent, or a series of such identifiers linked by the
 UINamingContainer.getSeparatorChar(jakarta.faces.context.FacesContext) character value. The search algorithm should operates as follows, though
 alternate alogrithms may be used as long as the end result is the same:
 
UIComponent that will be the base for searching, by stopping as soon as one of the following
 conditions is met:
 UIComponent of the component tree. The leading separator character will be stripped
 off, and the remainder of the search expression will be treated as a "relative" search expression as described
 below.UIComponent is a NamingContainer it will serve as the basis.NamingContainer is encountered, it will be the
 base.NamingContainer is encountered) the root UIComponent will be the base.id that matches, within the scope of the base
 component. The match is performed as follows:
 id property, and then
 recursively through the facets and children of the base UIComponent (except that if a descendant
 NamingContainer is found, its own facets and children are not searched).NamingContainer by the rules in the previous bullet point. Then, the
 findComponent() method of this NamingContainer will be called, passing the remainder of the
 search expression.expr - Search expression identifying the UIComponent to be returnedUIComponent, or null if the component was not found.IllegalArgumentException - if an intermediate identifier in a search expression identifies a
 UIComponent that is not a NamingContainerNullPointerException - if expr is nullpublic boolean invokeOnComponent(FacesContext context, String clientId, ContextCallback callback) throws FacesException
 Starting at this component in the View hierarchy, search for a component
 with a clientId equal to the argument clientId and, if found, call the
 ContextCallback.invokeContextCallback(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent) method on the argument callback, passing the current
 FacesContext and the found component as arguments. This method is similar to findComponent(java.lang.String) but it
 does not support the leading UINamingContainer.getSeparatorChar(jakarta.faces.context.FacesContext) syntax for searching from the root of the
 View.
 
 The default implementation will first check if this.getClientId() is equal to the argument
 clientId. If so, first call pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent), then call
 the ContextCallback.invokeContextCallback(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent) method on the argument callback, passing through the
 FacesContext argument and passing this as the component argument. Then
 call popComponentFromEL(jakarta.faces.context.FacesContext). If an Exception is thrown by the callback, wrap it in a
 FacesException and re-throw it. Otherwise, return true.
 
 Otherwise, for each component returned by getFacetsAndChildren(), call invokeOnComponent()
 passing the arguments to this method, in order. The first time invokeOnComponent() returns true, abort
 traversing the rest of the Iterator and return true.
 
 When calling ContextCallback.invokeContextCallback(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent) the implementation of this method must guarantee that the
 state of the component passed to the callback correctly reflects the component's position in the View hierarchy with
 respect to any state found in the argument clientId. For example, an iterating component such as
 UIData will need to set its row index to correctly reflect the argument clientId before finding
 the appropriate child component backed by the correct row. When the callback returns, either normally or by throwing
 an Exception the implementation of this method must restore the state of the view to the way it was
 before invoking the callback.
 
 If none of the elements from getFacetsAndChildren() returned true from
 invokeOnComponent(), return false.
 
 Simple usage example to find a component by clientId.
 
 
    private UIComponent found = null;
    private void doFind(FacesContext context, String clientId) {
      context.getViewRoot().invokeOnComponent(context, clientId,
          new ContextCallback() {
             public void invokeContextCallback(FacesContext context,
                                           UIComponent component) {
               found = component;
             }
          });
    }
 
 context - the FacesContext for the current requestclientId - the client identifier of the component to be passed to the argument callback.callback - an implementation of the Callback interface.true if the a component with the given clientId is found, the callback method was
 successfully invoked passing that component as an argument, and no Exception was thrown. Returns false
 if no component with the given clientId is found.NullPointerException - if any of the arguments are nullFacesException - if the argument Callback throws an Exception, it is wrapped in a FacesException
 and re-thrown.public abstract Map<String,UIComponent> getFacets()
 Return a mutable Map representing the facet UIComponents associated with this
 UIComponent, keyed by facet name (which must be a String). The returned implementation must support all of
 the standard and optional Map methods, plus support the following additional requirements:
 
Map implementation must implement the java.io.Serializable interface.null key or value must throw a NullPointerException.UIComponent must throw a ClassCastException.UIComponent is added:
 parent property of the component must be set to this component instance.parent property of the component was already non-null, the component must first be removed
 from its previous parent (where it may have been either a child or a facet).UIComponent is removed:
 parent property of the facet must be set to null.public int getFacetCount()
 Return the number of facet UIComponents that are associated with this UIComponent. If there are no
 facets, this method must return 0. The method must not cause the creation of a facet component map.
 
 For backwards compatability with classes that extend UIComponent directly, a default implementation is provided that
 simply calls getFacets() and then calls the size() method on the returned Map. A
 more optimized version of this method is provided in UIComponentBase.getFacetCount().
public abstract UIComponent getFacet(String name)
 Convenience method to return the named facet, if it exists, or null otherwise. If the requested facet
 does not exist, the facets Map must not be created.
 
name - Name of the desired facetnull.public abstract Iterator<UIComponent> getFacetsAndChildren()
 Return an Iterator over the facet followed by child UIComponents of this UIComponent.
 Facets are returned in an undefined order, followed by all the children in the order they are stored in the child
 list. If this component has no facets or children, an empty Iterator is returned.
 
 The returned Iterator must not support the remove() operation.
 
public abstract void broadcast(FacesEvent event) throws AbortProcessingException
 Broadcast the specified FacesEvent to all registered event listeners who have expressed an interest in events
 of this type. Listeners are called in the order in which they were added.
 
 If the event is an instance of BehaviorEvent and the current
 component is the source of the event call
 BehaviorEvent.getBehavior() to get the Behavior
 for the event.
 Call
 Behavior.broadcast(jakarta.faces.event.BehaviorEvent) on the
 Behavior instance.
 
event - The FacesEvent to be broadcastAbortProcessingException - Signal the Jakarta Server Faces implementation that no further processing on the
 current event should be performedIllegalArgumentException - if the implementation class of this FacesEvent is not supported by this
 componentNullPointerException - if event is nullpublic abstract void decode(FacesContext context)
 Decode any new state of this UIComponent from the request contained in the specified FacesContext,
 and store this state as needed.
 
 During decoding, events may be enqueued for later processing (by event listeners who have registered an interest), by
 calling queueEvent().
 
context - FacesContext for the request we are processingNullPointerException - if context is nullpublic boolean visitTree(VisitContext visitContext, VisitCallback callback)
Perform a tree visit starting at this node in the tree.
 UIComponent.visitTree() implementations do not invoke the VisitCallback directly, but instead call
 VisitContext.invokeVisitCallback(jakarta.faces.component.UIComponent, jakarta.faces.component.visit.VisitCallback) to invoke the callback. This allows VisitContext implementations to
 provide optimized tree traversals, for example by only calling the VisitCallback for a subset of components.
 
UIComponent.visitTree() implementations must call UIComponent.pushComponentToEL() before performing the visit and UIComponent.popComponentFromEL() after the visit.
visitContext - the VisitContext for this visitcallback - the VisitCallback instance whose visit method will be called for each node
 visited.true to indicate that the tree visit is complete (eg. all
 components that need to be visited have been visited). This results in the tree visit being short-circuited such that
 no more components are visited.
 VisitContext.invokeVisitCallback()protected boolean isVisitable(VisitContext context)
 Return true if this component should be visited, false otherwise. Called by
 UIComponent.visitTree() to determine whether this component satisfies the hints
 returned by VisitContext.getHints().
 
If this method returns false, the tree visited is short-circuited such that neither the component nor any of its descendents will be visited
 Custom visitTree() implementations may call this method to determine whether the component is visitable
 before performing any visit-related processing.
 
context - the Visit context.true if visitable, false otherwise.public abstract void encodeBegin(FacesContext context) throws IOException
 If our rendered property is true, render the
 beginning of the current state of this UIComponent to the response contained in the specified
 FacesContext. Call
 pushComponentToEL(jakarta.faces.context.FacesContext,jakarta.faces.component.UIComponent). Call
 Application.publishEvent(jakarta.faces.context.FacesContext, java.lang.Class<? extends jakarta.faces.event.SystemEvent>, java.lang.Object), passing
 PreRenderComponentEvent.class as the first argument and the component
 instance to be rendered as the second argument.
 
 If a Renderer is associated with this UIComponent, the actual encoding will be delegated to
 Renderer.encodeBegin(FacesContext, UIComponent).
 
 If our rendered property is false, call
 pushComponentToEL(jakarta.faces.context.FacesContext,jakarta.faces.component.UIComponent) and return
 immediately.
 
context - FacesContext for the response we are creatingIOException - if an input/output error occurs while renderingNullPointerException - if context is nullpublic abstract void encodeChildren(FacesContext context) throws IOException
 If our rendered property is true, render the child UIComponents of this
 UIComponent. This method will only be called if the rendersChildren property is
 true.
 
 If a Renderer is associated with this UIComponent, the actual encoding will be delegated to
 Renderer.encodeChildren(FacesContext, UIComponent). If no Renderer
 is associated with this UIComponent, iterate over each of the children of this component and call
 encodeAll(jakarta.faces.context.FacesContext).
 
context - FacesContext for the response we are creatingIOException - if an input/output error occurs while renderingNullPointerException - if context is nullpublic abstract void encodeEnd(FacesContext context) throws IOException
 If our rendered property is true, render the
 ending of the current state of this UIComponent.
 
 If a Renderer is associated with this UIComponent, the actual encoding will be delegated to
 Renderer.encodeEnd(FacesContext, UIComponent).
 
 Call popComponentFromEL(jakarta.faces.context.FacesContext). before returning regardless of the value of the rendered
 property.
 
context - FacesContext for the response we are creatingIOException - if an input/output error occurs while renderingNullPointerException - if context is nullpublic void encodeAll(FacesContext context) throws IOException
 If this component returns true from isRendered(), take the following action.
 
 Render this component and all its children that return true from isRendered(), regardless
 of the value of the getRendersChildren() flag.
 
context - the Faces context.IOException - if an input/output error occurs while renderingNullPointerException - if context is nullpublic void pushComponentToEL(FacesContext context, UIComponent component)
 Push the current UIComponent this to the FacesContext attribute map using the key
 CURRENT_COMPONENT saving the previous UIComponent associated with CURRENT_COMPONENT
 for a subsequent call to popComponentFromEL(jakarta.faces.context.FacesContext).
 
 This method and popComponentFromEL() form the basis for the contract that enables the Jakarta Expression
 Language Expression "#{component}" to resolve to the "current" component that is being processed in the
 lifecycle. The requirements for when pushComponentToEL() and popComponentFromEL() must be
 called are specified as needed in the javadoc for this class.
 
 After pushComponentToEL() returns, a call to getCurrentComponent(jakarta.faces.context.FacesContext) must return this
 UIComponent instance until popComponentFromEL() is called, after which point the previous
 UIComponent instance will be returned from getCurrentComponent()
 
context - the FacesContext for the current requestcomponent - the component to push to the EL. If component is null the
 UIComponent instance that this call was invoked upon will be pushed to the EL.NullPointerException - if context is nullFacesContext.getAttributes()public void popComponentFromEL(FacesContext context)
 Pop the current UIComponent from the FacesContext attributes map so that the previous
 UIComponent, if any, becomes the current component.
 
context - the FacesContext for the current requestNullPointerException - if context is nullFacesContext.getAttributes()public static boolean isCompositeComponent(UIComponent component)
 Return true if component is a composite component, otherwise false.
 
component - the UIComponent to testtrue if this is a composite component, false otherwise.NullPointerException - if component is nullpublic static UIComponent getCompositeComponentParent(UIComponent component)
Finds the nearest composite component parent of the specified component.
component - the component from which to start the search fromcomponent is null, return null, otherwise search the component's
 parent hierachy for the nearest parent composite component. If no parent composite component is found, return
 nullpublic static UIComponent getCurrentComponent(FacesContext context)
 Return the UIComponent instance that is currently processing. This is equivalent to evaluating the
 Jakarta Expression Language expression "#{component}" and doing a getValue operation on the
 resultant ValueExpression.
 
 This method must return null if there is no currently processing UIComponent
 
context - FacesContext for the request we are processingnull.NullPointerException - if context is nullpublic static UIComponent getCurrentCompositeComponent(FacesContext context)
 Return the closest ancestor component, relative to the component returned from getCurrentComponent(jakarta.faces.context.FacesContext), that is
 a composite component, or null if no such component exists.
 
context - FacesContext for the request we are processingnull.NullPointerException - if context is nullprotected abstract void addFacesListener(FacesListener listener)
 Add the specified FacesListener to the set of listeners registered to receive event notifications from this
 UIComponent. It is expected that UIComponent classes acting as event sources will have corresponding
 typesafe APIs for registering listeners of the required type, and the implementation of those registration methods
 will delegate to this method. For example:
 
 public class FooEvent extends FacesEvent { ... }
 public interface FooListener extends FacesListener {
   public void processFoo(FooEvent event);
 }
 public class FooComponent extends UIComponentBase {
   ...
   public void addFooListener(FooListener listener) {
     addFacesListener(listener);
   }
   public void removeFooListener(FooListener listener) {
     removeFacesListener(listener);
   }
   ...
 }
 listener - The FacesListener to be registeredNullPointerException - if listener is nullprotected abstract FacesListener[] getFacesListeners(Class clazz)
 Return an array of registered FacesListeners that are instances of the specified class. If there are no such
 registered listeners, a zero-length array is returned. The returned array can be safely be cast to an array strongly
 typed to an element type of clazz.
 
clazz - Class that must be implemented by a FacesListener for it to be returnedIllegalArgumentException - if class is not, and does not implement, FacesListenerNullPointerException - if clazz is nullprotected abstract void removeFacesListener(FacesListener listener)
 Remove the specified FacesListener from the set of listeners registered to receive event notifications from
 this UIComponent.
listener - The FacesListener to be deregisteredNullPointerException - if listener is nullpublic abstract void queueEvent(FacesEvent event)
 Queue an event for broadcast at the end of the current request processing lifecycle phase. The default implementation
 in UIComponentBase must delegate this call to the queueEvent() method of the parent
 UIComponent.
 
event - FacesEvent to be queuedIllegalStateException - if this component is not a descendant of a UIViewRootNullPointerException - if event is nullpublic void subscribeToEvent(Class<? extends SystemEvent> eventClass, ComponentSystemEventListener componentListener)
 This implementation throws UnsupportedOperationException and is provided for the sole purpose of not
 breaking existing applications that extend this class. UIComponentBase provides the implementation of this
 method.
 
eventClass - the event class.componentListener - the listener.public void unsubscribeFromEvent(Class<? extends SystemEvent> eventClass, ComponentSystemEventListener componentListener)
 This implementation throws UnsupportedOperationException and is provided for the sole purpose of not
 breaking existing applications that extend this class. UIComponentBase provides the implementation of this
 method.
 
eventClass - the event class.componentListener - the component listener.public List<SystemEventListener> getListenersForEventClass(Class<? extends SystemEvent> eventClass)
 This implementation throws UnsupportedOperationException and is provided for the sole purpose of not
 breaking existing applications that extend this class. UIComponentBase provides the implementation of this
 method.
 
getListenersForEventClass in interface SystemEventListenerHoldereventClass - the event class.public UIComponent getNamingContainer()
 Starting with "this", return the closest component in the ancestry that is a NamingContainer or
 null if none can be found.
 
null.public abstract void processRestoreState(FacesContext context, Object state)
Perform the component tree processing required by the Restore View phase of the request processing lifecycle for all facets of this component, all children of this component, and this component itself, as follows.
restoreState() method of this component.pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent).processRestoreState() method of all facets and children of this UIComponent in the
 order determined by a call to getFacetsAndChildren(). After returning
 from the processRestoreState() method on a child or facet, call
 popComponentFromEL(jakarta.faces.context.FacesContext)This method may not be called if the state saving method is set to server.
context - FacesContext for the request we are processingstate - the state.NullPointerException - if context is nullpublic abstract void processDecodes(FacesContext context)
Perform the component tree processing required by the Apply Request Values phase of the request processing lifecycle for all facets of this component, all children of this component, and this component itself, as follows.
rendered property of this UIComponent is false, skip further
 processing.pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent).processDecodes() method of all facets and children of this UIComponent, in the
 order determined by a call to getFacetsAndChildren().decode() method of this component.popComponentFromEL(jakarta.faces.context.FacesContext) from inside of a finally block, just before returning.RuntimeException is thrown during decode processing, call FacesContext.renderResponse()
 and re-throw the exception.context - FacesContext for the request we are processingNullPointerException - if context is nullpublic void processEvent(ComponentSystemEvent event) throws AbortProcessingException
 The default implementation performs the following action. If the argument event is an instance of
 PostRestoreStateEvent, call this.getValueExpression(java.lang.String) passing the literal string
 “binding”, without the quotes, as the argument. If the result is non-null, set the value of
 the ValueExpression to be this.
 
processEvent in interface ComponentSystemEventListenerevent - the ComponentSystemEvent instance that is being processed.AbortProcessingException - if lifecycle processing should cease for this request.public abstract void processValidators(FacesContext context)
Perform the component tree processing required by the Process Validations phase of the request processing lifecycle for all facets of this component, all children of this component, and this component itself, as follows.
rendered property of this UIComponent is false, skip further
 processing.pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent).processValidators() method of all facets and children of this UIComponent, in the
 order determined by a call to getFacetsAndChildren().getFacetsAndChildren() call
 popComponentFromEL(jakarta.faces.context.FacesContext).context - FacesContext for the request we are processingNullPointerException - if context is nullPreValidateEvent, 
PostValidateEventpublic abstract void processUpdates(FacesContext context)
Perform the component tree processing required by the Update Model Values phase of the request processing lifecycle for all facets of this component, all children of this component, and this component itself, as follows.
rendered property of this UIComponent is false, skip further
 processing.pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent).processUpdates() method of all facets and children of this UIComponent, in the
 order determined by a call to getFacetsAndChildren(). After returning
 from the processUpdates() method on a child or facet, call
 popComponentFromEL(jakarta.faces.context.FacesContext)context - FacesContext for the request we are processingNullPointerException - if context is nullpublic abstract Object processSaveState(FacesContext context)
Perform the component tree processing required by the state saving portion of the Render Response phase of the request processing lifecycle for all facets of this component, all children of this component, and this component itself, as follows.
transient property of this component. If true, just return null.pushComponentToEL(jakarta.faces.context.FacesContext, jakarta.faces.component.UIComponent).processSaveState() method of all facets and children of this UIComponent in the
 order determined by a call to getFacetsAndChildren(), skipping children and facets that are transient.
 Ensure that popComponentFromEL(jakarta.faces.context.FacesContext) is called correctly after each child or facet.saveState() method of this component.This method may not be called if the state saving method is set to server.
context - FacesContext for the request we are processingNullPointerException - if context is nullprotected abstract FacesContext getFacesContext()
 Convenience method to return the FacesContext instance for the current request.
 
protected abstract Renderer getRenderer(FacesContext context)
 Convenience method to return the Renderer instance associated with this component, if any; otherwise, return
 null.
 
context - FacesContext for the current requestnull.@Deprecated public abstract ValueBinding getValueBinding(String name)
getValueExpression(java.lang.String).
 Call through to getValueExpression(java.lang.String) and examine the result. If the result is an instance of the wrapper class
 mandated in setValueBinding(java.lang.String, jakarta.faces.el.ValueBinding), extract the ValueBinding instance and return it. Otherwise, wrap
 the result in an implementation of ValueBinding, and return it.
 
name - Name of the attribute or property for which to retrieve a ValueBindingNullPointerException - if name is null@Deprecated public abstract void setValueBinding(String name, ValueBinding binding)
setValueExpression(java.lang.String, jakarta.el.ValueExpression).
 Wrap the argument binding in an implementation of ValueExpression and call through to
 setValueExpression(java.lang.String, jakarta.el.ValueExpression).
 
name - Name of the attribute or property for which to set a ValueBindingbinding - The ValueBinding to set, or null to remove any currently set ValueBindingIllegalArgumentException - if name is one of id or parentNullPointerException - if name is nullCopyright © 2018,2020 Eclipse Foundation.
Use is subject to license terms.