Class UIComponent

java.lang.Object
jakarta.faces.component.UIComponent
All Implemented Interfaces:
PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, EventListener
Direct Known Subclasses:
UIComponentBase

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

  • Field Details

    • HONOR_CURRENT_COMPONENT_ATTRIBUTES_PARAM_NAME

      public 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.

      See Also:
    • BEANINFO_KEY

      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.

      Since:
      2.0
      See Also:
    • FACETS_KEY

      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.

      Since:
      2.0
      See Also:
    • VIEW_LOCATION_KEY

      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.

      Since:
      2.0
      See Also:
    • COMPOSITE_COMPONENT_TYPE_KEY

      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.

      Since:
      2.0
      See Also:
    • COMPOSITE_FACET_NAME

      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.

      Since:
      2.0
      See Also:
    • ATTRS_WITH_DECLARED_DEFAULT_VALUES

      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.

      Since:
      2.1
      See Also:
    • CURRENT_COMPONENT

      @Deprecated public static final String CURRENT_COMPONENT
      Deprecated.

      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.

      Since:
      2.0
      See Also:
    • CURRENT_COMPOSITE_COMPONENT

      @Deprecated public static final String CURRENT_COMPOSITE_COMPONENT
      Deprecated.

      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.

      Since:
      2.0
      See Also:
    • bindings

      @Deprecated protected Map<String,ValueExpression> bindings
      Deprecated.
  • Constructor Details

    • UIComponent

      public UIComponent()
  • Method Details

    • getAttributes

      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:

      • The Map implementation must implement the java.io.Serializable interface.
      • 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 a ClassCastException.
      • If the attribute name specified as a key matches a property of this 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.
      Returns:
      the component attribute map.
    • getPassThroughAttributes

      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.

      Returns:
      the pass-through attribute map.
      Since:
      2.2
    • getPassThroughAttributes

      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.

      Parameters:
      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.
      Returns:
      A Map instance, or null.
      Since:
      2.2
    • getValueExpression

      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.

      Parameters:
      name - Name of the attribute or property for which to retrieve a ValueExpression
      Returns:
      the value expression, or null.
      Throws:
      NullPointerException - if name is null
      Since:
      1.2
    • setValueExpression

      public 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.getAttributes().put(name, value) where 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.

      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 or parent
      NullPointerException - if name is null
      Since:
      1.2
    • markInitialState

      public 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.

      Specified by:
      markInitialState in interface PartialStateHolder
      Since:
      2.0
    • initialStateMarked

      public boolean initialStateMarked()

      An implementation of PartialStateHolder.initialStateMarked(), this method is called by the runtime to test if the PartialStateHolder.markInitialState() method was called.

      Specified by:
      initialStateMarked in interface PartialStateHolder
      Returns:
      true if the initial state is marked, false otherwise.
      Since:
      2.0
    • clearInitialState

      public void clearInitialState()

      An implementation of PartialStateHolder.clearInitialState(), this method is called by the runtime to tell the instance to stop tracking state changes.

      Specified by:
      clearInitialState in interface PartialStateHolder
      Since:
      2.0
    • getStateHelper

      protected StateHelper getStateHelper()

      Return the StateHelper instance used to help this component implement PartialStateHolder.

      Returns:
      the state helper.
      Since:
      2.0
    • getStateHelper

      protected StateHelper getStateHelper(boolean create)

      Like getStateHelper(), but only create a state helper instance if the argument creat is true.

      Parameters:
      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.
      Returns:
      the state helper.
      Since:
      2.0
    • getTransientStateHelper

      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.

      Returns:
      the transient state helper.
      Since:
      2.1
    • getTransientStateHelper

      public TransientStateHelper getTransientStateHelper(boolean create)

      Return the TransientStateHelper instance for this UIComponent instance.

      Parameters:
      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.
      Returns:
      the transient state helper.
      Since:
      2.1
    • restoreTransientState

      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).

      Specified by:
      restoreTransientState in interface TransientStateHolder
      Parameters:
      context - the Faces context
      state - the object containing transient values
      Since:
      2.1
    • saveTransientState

      public 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.

      Specified by:
      saveTransientState in interface TransientStateHolder
      Parameters:
      context - the Faces context.
      Returns:
      object containing transient values
      Since:
      2.1
    • isInView

      public boolean isInView()

      Return true if this component is within the view hierarchy otherwise false

      Returns:
      true if within a view hierarchy, false otherwise.
      Since:
      2.0
    • setInView

      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.

      Parameters:
      isInView - flag indicating whether or not this component is within the view hierachy
      Since:
      2.0
    • getClientId

      public 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).

      Returns:
      the client id.
      Since:
      2.0
    • getClientId

      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 + UINamingContainer.getSeparatorChar(jakarta.faces.context.FacesContext) + myId. Call Renderer.convertClientId(jakarta.faces.context.FacesContext, java.lang.String), passing myId, and return the result.

      Parameters:
      context - The FacesContext for the current request
      Returns:
      the client id.
      Throws:
      NullPointerException - if context is null
    • getContainerClientId

      public 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.

      Parameters:
      context - the Faces context.
      Returns:
      the container client id.
      Throws:
      NullPointerException - if context is null
      Since:
      1.2
    • getFamily

      public 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

      Returns:
      the component family (not null).
    • getId

      public abstract String getId()

      Return the component identifier of this UIComponent.

      Returns:
      the component identifier.
    • setId

      public abstract void setId(String id)

      Set the component identifier of this UIComponent (if any). Component identifiers must obey the following syntax restrictions:

      • Must not be a zero-length String.
      • First character must be a letter or an underscore ('_').
      • Subsequent characters must be a letter, a digit, an underscore ('_'), or a dash ('-').

      Component identifiers must also obey the following semantic restrictions (note that this restriction is NOT enforced by the setId() implementation):

      • The specified identifier must be unique among all the components (including facets) that are descendents of the nearest ancestor UIComponent that is a NamingContainer, or within the scope of the entire component tree if there is no such ancestor that is a NamingContainer.
      Parameters:
      id - The new component identifier, or null to indicate that this UIComponent does not have a component identifier
      Throws:
      IllegalArgumentException - if id is not syntactically valid
    • getParent

      public 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( ).

      Returns:
      the parent component.
    • setParent

      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.

      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.

      Parameters:
      parent - The new parent, or null for the root node of a component tree
    • isRendered

      public abstract boolean isRendered()

      Return true if this component (and its children) should be rendered during the Render Response phase of the request processing lifecycle.

      Returns:
      true if the component should be rendered, false otherwise.
    • setRendered

      public abstract void setRendered(boolean rendered)

      Set the rendered property of this UIComponent.

      Parameters:
      rendered - If true render this component; otherwise, do not render this component
    • getRendererType

      public abstract String getRendererType()

      Return the Renderer type for this UIComponent (if any).

      Returns:
      the renderer type.
    • setRendererType

      public abstract void setRendererType(String rendererType)

      Set the Renderer type for this UIComponent, or null for components that render themselves.

      Parameters:
      rendererType - Logical identifier of the type of Renderer to use, or null for components that render themselves
    • getRendersChildren

      public 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).

      Returns:
      true if the component renders its children, false otherwise.
    • getResourceBundleMap

      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.

      Returns:
      the resource bundle map.
      Since:
      2.0
    • getChildren

      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:

      Returns:
      the list of children.
    • getChildCount

      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.

      Returns:
      the number of child components.
    • findComponent

      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:

      • Identify the UIComponent that will be the base for searching, by stopping as soon as one of the following conditions is met:
        • If the search expression begins with the the separator character (called an "absolute" search expression), the base will be the root 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.
        • Otherwise, if this UIComponent is a NamingContainer it will serve as the basis.
        • Otherwise, search up the parents of this component. If a NamingContainer is encountered, it will be the base.
        • Otherwise (if no NamingContainer is encountered) the root UIComponent will be the base.
      • The search expression (possibly modified in the previous step) is now a "relative" search expression that will be used to locate the component (if any) that has an id that matches, within the scope of the base component. The match is performed as follows:
        • If the search expression is a simple identifier, this value is compared to the 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).
        • If the search expression includes more than one identifier separated by the separator character, the first identifier is used to locate a 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.
      Parameters:
      expr - Search expression identifying the UIComponent to be returned
      Returns:
      the found UIComponent, or null if the component was not found.
      Throws:
      IllegalArgumentException - if an intermediate identifier in a search expression identifies a UIComponent that is not a NamingContainer
      NullPointerException - if expr is null
    • invokeOnComponent

      public 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;
                   }
                });
          }
       
       
      Parameters:
      context - the FacesContext for the current request
      clientId - the client identifier of the component to be passed to the argument callback.
      callback - an implementation of the Callback interface.
      Returns:
      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.
      Throws:
      NullPointerException - if any of the arguments are null
      FacesException - if the argument Callback throws an Exception, it is wrapped in a FacesException and re-thrown.
      Since:
      1.2
    • getFacets

      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:

      • The Map implementation must implement the java.io.Serializable interface.
      • 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 a ClassCastException.
      • Any attempt to add a value that is not a UIComponent must throw a ClassCastException.
      • Whenever a new facet UIComponent is added:
        • The parent property of the component must be set to this component instance.
        • If the 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).
      • Whenever an existing facet UIComponent is removed:
        • The parent property of the facet must be set to null.
      Returns:
      the map of facets.
    • getFacetCount

      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().

      Returns:
      the number of facets.
      Since:
      1.2
    • getFacet

      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.

      Parameters:
      name - Name of the desired facet
      Returns:
      the component, or null.
    • getFacetsAndChildren

      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.

      Returns:
      the facets and children iterator.
    • broadcast

      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.

      Parameters:
      event - The FacesEvent to be broadcast
      Throws:
      AbortProcessingException - Signal the Jakarta Server Faces implementation that no further processing on the current event should be performed
      IllegalArgumentException - if the implementation class of this FacesEvent is not supported by this component
      NullPointerException - if event is null
    • decode

      public 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().

      Parameters:
      context - FacesContext for the request we are processing
      Throws:
      NullPointerException - if context is null
    • visitTree

      public 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.

      Parameters:
      visitContext - the VisitContext for this visit
      callback - the VisitCallback instance whose visit method will be called for each node visited.
      Returns:
      component implementations may return 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.
      Since:
      2.0
      See Also:
    • isVisitable

      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.

      Parameters:
      context - the Visit context.
      Returns:
      true if visitable, false otherwise.
      Since:
      2.0
    • encodeBegin

      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.

      Parameters:
      context - FacesContext for the response we are creating
      Throws:
      IOException - if an input/output error occurs while rendering
      NullPointerException - if context is null
    • encodeChildren

      public 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).

      Parameters:
      context - FacesContext for the response we are creating
      Throws:
      IOException - if an input/output error occurs while rendering
      NullPointerException - if context is null
    • encodeEnd

      public 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.

      Parameters:
      context - FacesContext for the response we are creating
      Throws:
      IOException - if an input/output error occurs while rendering
      NullPointerException - if context is null
    • encodeAll

      public 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.

      Parameters:
      context - the Faces context.
      Throws:
      IOException - if an input/output error occurs while rendering
      NullPointerException - if context is null
      Since:
      1.2
    • pushComponentToEL

      public 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()

      Parameters:
      context - the FacesContext for the current request
      component - 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.
      Throws:
      NullPointerException - if context is null
      Since:
      2.0
      See Also:
    • popComponentFromEL

      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.

      Parameters:
      context - the FacesContext for the current request
      Throws:
      NullPointerException - if context is null
      Since:
      2.0
      See Also:
    • isCompositeComponent

      public static boolean isCompositeComponent(UIComponent component)

      Return true if component is a composite component, otherwise false.

      Parameters:
      component - the UIComponent to test
      Returns:
      true if this is a composite component, false otherwise.
      Throws:
      NullPointerException - if component is null
      Since:
      2.0
    • getCompositeComponentParent

      public static UIComponent getCompositeComponentParent(UIComponent component)

      Finds the nearest composite component parent of the specified component.

      Parameters:
      component - the component from which to start the search from
      Returns:
      if component 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 null
      Since:
      2.0
    • getCurrentComponent

      public 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

      Parameters:
      context - FacesContext for the request we are processing
      Returns:
      the current component, or null.
      Throws:
      NullPointerException - if context is null
      Since:
      2.0
    • getCurrentCompositeComponent

      public 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.

      Parameters:
      context - FacesContext for the request we are processing
      Returns:
      the current composite component, or null.
      Throws:
      NullPointerException - if context is null
      Since:
      2.0
    • addFacesListener

      protected 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);
         }
         ...
       }
       
      Parameters:
      listener - The FacesListener to be registered
      Throws:
      NullPointerException - if listener is null
    • getFacesListeners

      protected 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.

      Parameters:
      clazz - Class that must be implemented by a FacesListener for it to be returned
      Returns:
      the Faces listeners, or a zero-length array.
      Throws:
      IllegalArgumentException - if class is not, and does not implement, FacesListener
      NullPointerException - if clazz is null
    • removeFacesListener

      protected abstract void removeFacesListener(FacesListener listener)

      Remove the specified FacesListener from the set of listeners registered to receive event notifications from this UIComponent.

      Parameters:
      listener - The FacesListener to be deregistered
      Throws:
      NullPointerException - if listener is null
    • queueEvent

      public 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.

      Parameters:
      event - FacesEvent to be queued
      Throws:
      IllegalStateException - if this component is not a descendant of a UIViewRoot
      NullPointerException - if event is null
    • subscribeToEvent

      public 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.

      Parameters:
      eventClass - the event class.
      componentListener - the listener.
      Since:
      2.1
    • unsubscribeFromEvent

      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.

      Parameters:
      eventClass - the event class.
      componentListener - the component listener.
      Since:
      2.1
    • getListenersForEventClass

      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.

      Specified by:
      getListenersForEventClass in interface SystemEventListenerHolder
      Parameters:
      eventClass - the event class.
      Returns:
      the list of listeners.
      Since:
      2.1
    • getNamingContainer

      public UIComponent getNamingContainer()

      Starting with "this", return the closest component in the ancestry that is a NamingContainer or null if none can be found.

      Returns:
      the naming container, or null.
      Since:
      2.0
    • processRestoreState

      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.

      This method may not be called if the state saving method is set to server.

      Parameters:
      context - FacesContext for the request we are processing
      state - the state.
      Throws:
      NullPointerException - if context is null
    • processDecodes

      public 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.

      Parameters:
      context - FacesContext for the request we are processing
      Throws:
      NullPointerException - if context is null
    • processEvent

      public 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.

      Specified by:
      processEvent in interface ComponentSystemEventListener
      Parameters:
      event - the ComponentSystemEvent instance that is being processed.
      Throws:
      AbortProcessingException - if lifecycle processing should cease for this request.
    • processValidators

      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.

      Parameters:
      context - FacesContext for the request we are processing
      Throws:
      NullPointerException - if context is null
      See Also:
    • processUpdates

      public 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.

      Parameters:
      context - FacesContext for the request we are processing
      Throws:
      NullPointerException - if context is null
    • processSaveState

      public 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.

      This method may not be called if the state saving method is set to server.

      Parameters:
      context - FacesContext for the request we are processing
      Returns:
      the saved state.
      Throws:
      NullPointerException - if context is null
    • getFacesContext

      protected abstract FacesContext getFacesContext()

      Convenience method to return the FacesContext instance for the current request.

      Returns:
      the Faces context.
    • getRenderer

      protected abstract Renderer getRenderer(FacesContext context)

      Convenience method to return the Renderer instance associated with this component, if any; otherwise, return null.

      Parameters:
      context - FacesContext for the current request
      Returns:
      the renderer, or null.
    • getValueBinding

      @Deprecated public abstract ValueBinding getValueBinding(String name)
      Deprecated.
      This has been replaced by 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.

      Parameters:
      name - Name of the attribute or property for which to retrieve a ValueBinding
      Returns:
      the value binding.
      Throws:
      NullPointerException - if name is null
    • setValueBinding

      @Deprecated public abstract void setValueBinding(String name, ValueBinding binding)

      Wrap the argument binding in an implementation of ValueExpression and call through to setValueExpression(java.lang.String, jakarta.el.ValueExpression).

      Parameters:
      name - Name of the attribute or property for which to set a ValueBinding
      binding - The ValueBinding to set, or null to remove any currently set ValueBinding
      Throws:
      IllegalArgumentException - if name is one of id or parent
      NullPointerException - if name is null