Class UIComponentBase

java.lang.Object
jakarta.faces.component.UIComponent
jakarta.faces.component.UIComponentBase
All Implemented Interfaces:
PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, EventListener
Direct Known Subclasses:
UIColumn, UICommand, UIData, UIForm, UIGraphic, UIImportConstants, UIMessage, UIMessages, UINamingContainer, UIOutput, UIPanel, UIParameter, UISelectItem, UISelectItems, UIViewAction, UIViewRoot, UIWebsocket

@JSFComponent(type="jakarta.faces.ComponentBase", family="jakarta.faces.ComponentBase", desc="base component when all components must inherit", tagClass="jakarta.faces.webapp.UIComponentELTag", configExcluded=true) @JSFJspProperty(name="binding", returnType="jakarta.faces.component.UIComponent", longDesc="Identifies a backing bean property (of type UIComponent or appropriate subclass) to bind to this component instance. This value must be an EL expression.", desc="backing bean property to bind to this component instance") public abstract class UIComponentBase extends UIComponent
Standard implementation of the UIComponent base class; all standard Faces components extend this class.

Disclaimer: The official definition for the behaviour of this class is the Faces 1.1 specification but for legal reasons the specification cannot be replicated here. Any javadoc here therefore describes the current implementation rather than the spec, though this class has been verified as correctly implementing the spec. see Javadoc of Faces Specification for more.

  • Constructor Details

    • UIComponentBase

      public UIComponentBase()
  • Method Details

    • setId

      public void setId(String id)
      Set an identifier for this component which is unique within the scope of the nearest ancestor NamingContainer component. The id is not necessarily unique across all components in the current view.

      The id must start with an underscore if it is generated by the Faces framework, and must not start with an underscore if it has been specified by the user (eg in a JSP tag).

      The first character of the id must be an underscore or letter. Following characters may be letters, digits, underscores or dashes.

      Null is allowed as a parameter, and will reset the id to null.

      The clientId of this component is reset by this method; see getClientId for more info.

      Specified by:
      setId in class UIComponent
      Throws:
      IllegalArgumentException - if the id is not valid.
    • setParent

      public void setParent(UIComponent parent)

      Set the parent UIComponent of this UIComponent.

      Specified by:
      setParent in class UIComponent
      Parameters:
      parent - The new parent, or null for the root node of a component tree
    • addClientBehavior

      public void addClientBehavior(String eventName, ClientBehavior behavior)
      Parameters:
      eventName -
      behavior -
      Since:
      2.0
    • broadcast

      public void broadcast(FacesEvent event) throws AbortProcessingException
      Invoke any listeners attached to this object which are listening for an event whose type matches the specified event's runtime type.

      This method does not propagate the event up to parent components, ie listeners attached to parent components don't automatically get called.

      If any of the listeners throws AbortProcessingException then that exception will prevent any further listener callbacks from occurring, and the exception propagates out of this method without alteration.

      ActionEvent events are typically queued by the renderer associated with this component in its decode method; ValueChangeEvent events by the component's validate method. In either case the event's source property references a component. At some later time the UIViewRoot component iterates over its queued events and invokes the broadcast method on each event's source object.

      Specified by:
      broadcast in class UIComponent
      Parameters:
      event - must not be null.
      Throws:
      AbortProcessingException
    • clearInitialState

      public void clearInitialState()
      Description copied from class: UIComponent
      Specified by:
      clearInitialState in interface PartialStateHolder
      Overrides:
      clearInitialState in class UIComponent
    • decode

      public void decode(FacesContext context)
      Check the submitted form parameters for data associated with this component. This default implementation delegates to this component's renderer if there is one, and otherwise ignores the call.
      Specified by:
      decode in class UIComponent
    • encodeAll

      public void encodeAll(FacesContext context) throws IOException
      Overrides:
      encodeAll in class UIComponent
      Throws:
      IOException
    • encodeBegin

      public void encodeBegin(FacesContext context) throws IOException
      Specified by:
      encodeBegin in class UIComponent
      Throws:
      IOException
    • encodeChildren

      public void encodeChildren(FacesContext context) throws IOException
      Specified by:
      encodeChildren in class UIComponent
      Throws:
      IOException
    • encodeEnd

      public void encodeEnd(FacesContext context) throws IOException
      Specified by:
      encodeEnd in class UIComponent
      Throws:
      IOException
    • findComponent

      public UIComponent findComponent(String expr)
      Standard method for finding other components by id, inherited by most UIComponent objects.

      The lookup is performed in a manner similar to finding a file in a filesystem; there is a "base" at which to start, and the id can be for something in the "local directory", or can include a relative path. Here, NamingContainer components fill the role of directories, and ":" is the "path separator". Note, however, that although components have a strict parent/child hierarchy, component ids are only prefixed ("namespaced") with the id of their parent when the parent is a NamingContainer.

      The base node at which the search starts is determined as follows:

      • When expr starts with ':', the search starts with the root component of the tree that this component is in (ie the ancestor whose parent is null).
      • Otherwise, if this component is a NamingContainer then the search starts with this component.
      • Otherwise, the search starts from the nearest ancestor NamingContainer (or the root component if there is no NamingContainer ancestor).
      Specified by:
      findComponent in class UIComponent
      Parameters:
      expr - is of form "id1:id2:id3".
      Returns:
      UIComponent or null if no component with the specified id is found.
    • getAttributes

      public Map<String,Object> getAttributes()
      Get a map through which all the UIComponent's properties, value-bindings and non-property attributes can be read and written.

      When writing to the returned map:

      • If this component has an explicit property for the specified key then the setter method is called. An IllegalArgumentException is thrown if the property is read-only. If the property is readable then the old value is returned, otherwise null is returned.
      • Otherwise the key/value pair is stored in a map associated with the component.
      Note that value-bindings are not written by put calls to this map. Writing to the attributes map using a key for which a value-binding exists will just store the value in the attributes map rather than evaluating the binding, effectively "hiding" the value-binding from later attributes.get calls. Setter methods on components commonly do not evaluate a binding of the same name; they just store the provided value directly on the component.

      When reading from the returned map:

      • If this component has an explicit property for the specified key then the getter method is called. If the property exists, but is read-only (ie only a setter method is defined) then an IllegalArgumentException is thrown.
      • If the attribute map associated with the component has an entry with the specified key, then that is returned.
      • If this component has a value-binding for the specified key, then the value-binding is evaluated to fetch the value.
      • Otherwise, null is returned.
      Note that components commonly define getter methods such that they evaluate a value-binding of the same name if there isn't yet a local property.

      Assigning values to the map which are not explicit properties on the underlying component can be used to "tunnel" attributes from the JSP tag (or view-specific equivalent) to the associated renderer without modifying the component itself.

      Any value-bindings and non-property attributes stored in this map are automatically serialized along with the component when the view is serialized.

      Specified by:
      getAttributes in class UIComponent
    • getPassThroughAttributes

      public Map<String,Object> getPassThroughAttributes(boolean create)
      Overrides:
      getPassThroughAttributes in class UIComponent
      Returns:
      A Map instance, or null.
    • getChildCount

      public int getChildCount()
      Return the number of direct child components this component has.

      Identical to getChildren().size() except that when this component has no children this method will not force an empty list to be created.

      Specified by:
      getChildCount in class UIComponent
    • getChildren

      public List<UIComponent> getChildren()
      Return a list of the UIComponent objects which are direct children of this component.

      The list object returned has some non-standard behaviour:

      • The list is type-checked; only UIComponent objects can be added.
      • If a component is added to the list with an id which is the same as some other component in the list then an exception is thrown. However multiple components with a null id may be added.
      • The component's parent property is set to this component. If the component already had a parent, then the component is first removed from its original parent's child list.
      Specified by:
      getChildren in class UIComponent
    • getClientBehaviors

      public Map<String,List<ClientBehavior>> getClientBehaviors()
      Returns:
      Since:
      2.0
    • getClientId

      public String getClientId(FacesContext context)
      Get a string which can be output to the response which uniquely identifies this UIComponent within the current view.

      The component should have an id attribute already assigned to it; however if the id property is currently null then a unique id is generated and set for this component. This only happens when components are programmatically created without ids, as components created by a ViewHandler should be assigned ids when they are created.

      If this component is a descendant of a NamingContainer then the client id is of form "{namingContainerId}:{componentId}". Note that the naming container's id may itself be of compound form if it has an ancestor naming container. Note also that this only applies to naming containers; other UIComponent types in the component's ancestry do not affect the clientId.

      Finally the renderer associated with this component is asked to convert the id into a suitable form. This allows escaping of any characters in the clientId which are significant for the markup language generated by that renderer.

      Specified by:
      getClientId in class UIComponent
    • getDefaultEventName

      public String getDefaultEventName()
      Returns:
      Since:
      2.0
    • getEventNames

      public Collection<String> getEventNames()
      Returns:
      Since:
      2.0
    • getFacet

      public UIComponent getFacet(String name)
      Specified by:
      getFacet in class UIComponent
    • getFacetCount

      public int getFacetCount()
      Overrides:
      getFacetCount in class UIComponent
      Since:
      1.2
    • getFacets

      public Map<String,UIComponent> getFacets()
      Specified by:
      getFacets in class UIComponent
    • getFacetsAndChildren

      public Iterator<UIComponent> getFacetsAndChildren()
      Specified by:
      getFacetsAndChildren in class UIComponent
    • getId

      @JSFProperty(rtexprvalue=true) public String getId()
      Get a string which uniquely identifies this UIComponent within the scope of the nearest ancestor NamingContainer component. The id is not necessarily unique across all components in the current view.
      Specified by:
      getId in class UIComponent
    • getParent

      public UIComponent getParent()
      Description copied from class: UIComponent
      Returns the parent of the component. Children can be added to or removed from a component even if this method returns null for the child.
      Specified by:
      getParent in class UIComponent
    • getRendererType

      public String getRendererType()
      Specified by:
      getRendererType in class UIComponent
    • getRendersChildren

      public boolean getRendersChildren()
      Indicates whether this component or its renderer manages the invocation of the rendering methods of its child components. When this is true:
      • This component's encodeBegin method will only be called after all the child components have been created and added to this component.
      • This component's encodeChildren method will be called after its encodeBegin method. Components for which this method returns false do not get this method invoked at all.
      • No rendering methods will be called automatically on child components; this component is required to invoke the encodeBegin/encodeEnd/etc on them itself.
      Specified by:
      getRendersChildren in class UIComponent
    • invokeOnComponent

      public boolean invokeOnComponent(FacesContext context, String clientId, ContextCallback callback) throws FacesException
      invokeOnComponent must be implemented in UIComponentBase too...
      Overrides:
      invokeOnComponent in class UIComponent
      Parameters:
      context - FacesContext for the current request
      clientId - the id of the desired UIComponent clazz
      callback - Implementation of the ContextCallback to be called
      Returns:
      has component been found ?
      Throws:
      FacesException
    • visitTree

      public boolean visitTree(VisitContext context, VisitCallback callback)
      Description copied from class: UIComponent
      The visit tree method, visit tree walks over a subtree and processes the callback object to perform some operation on the subtree

      there are some details in the implementation which according to the spec have to be in place: a) before calling the callback and traversing into the subtree pushComponentToEL has to be called b) after the processing popComponentFromEL has to be performed to remove the component from the el

      The tree traversal optimizations are located in the visit context and can be replaced via the VisitContextFactory in the faces-config factory section

      Overrides:
      visitTree in class UIComponent
      Parameters:
      context - the visit context which handles the processing details
      callback - the callback to be performed
      Returns:
      false if the processing is not done true if we can shortcut the visiting because we are done with everything
    • isRendered

      @JSFProperty public boolean isRendered()
      A boolean value that indicates whether this component should be rendered. Default value: true.
      Specified by:
      isRendered in class UIComponent
    • isTransient

      @JSFProperty(literalOnly=true, istransient=true, tagExcluded=true) public boolean isTransient()
    • markInitialState

      public void markInitialState()
      Specified by:
      markInitialState in interface PartialStateHolder
      Overrides:
      markInitialState in class UIComponent
    • addFacesListener

      protected void addFacesListener(FacesListener listener)
      Specified by:
      addFacesListener in class UIComponent
    • getFacesContext

      protected FacesContext getFacesContext()
      Specified by:
      getFacesContext in class UIComponent
    • getFacesListeners

      protected FacesListener[] getFacesListeners(Class clazz)
      Specified by:
      getFacesListeners in class UIComponent
    • getRenderer

      protected Renderer getRenderer(FacesContext context)
      Specified by:
      getRenderer in class UIComponent
    • removeFacesListener

      protected void removeFacesListener(FacesListener listener)
      Specified by:
      removeFacesListener in class UIComponent
    • queueEvent

      public void queueEvent(FacesEvent event)
      Specified by:
      queueEvent in class UIComponent
    • processDecodes

      public void processDecodes(FacesContext context)
      Specified by:
      processDecodes in class UIComponent
    • processValidators

      public void processValidators(FacesContext context)
      Specified by:
      processValidators in class UIComponent
    • processUpdates

      public void processUpdates(FacesContext context)
      This isn't an input component, so just pass on the processUpdates call to child components and facets that might be input components.

      Components that were never rendered can't possibly be receiving update data (no corresponding fields were ever put into the response) so if this component is not rendered then this method does not invoke processUpdates on its children.

      Specified by:
      processUpdates in class UIComponent
    • processSaveState

      public Object processSaveState(FacesContext context)
      Specified by:
      processSaveState in class UIComponent
    • processRestoreState

      public void processRestoreState(FacesContext context, Object state)
      Specified by:
      processRestoreState in class UIComponent
    • setTransient

      public void setTransient(boolean transientFlag)
    • saveAttachedState

      public static Object saveAttachedState(FacesContext context, Object attachedObject)
      Serializes objects which are "attached" to this component but which are not UIComponent children of it. Examples are validator and listener objects. To be precise, it returns an object which implements java.io.Serializable, and which when serialized will persist the state of the provided object.

      If the attachedObject is a List then every object in the list is saved via a call to this method, and the returned wrapper object contains a List object.

      If the object implements StateHolder then the object's saveState is called immediately, and a wrapper is returned which contains both this saved state and the original class name. However in the case where the StateHolder.isTransient method returns true, null is returned instead.

      If the object implements java.io.Serializable then the object is simply returned immediately; standard java serialization will later be used to store this object.

      In all other cases, a wrapper is returned which simply stores the type of the provided object. When deserialized, a default instance of that type will be recreated.

    • restoreAttachedState

      public static Object restoreAttachedState(FacesContext context, Object stateObj) throws IllegalStateException
      Throws:
      IllegalStateException
    • saveState

      public Object saveState(FacesContext context)
      Invoked after the render phase has completed, this method returns an object which can be passed to the restoreState of some other instance of UIComponentBase to reset that object's state to the same values as this object currently has.
    • restoreState

      public void restoreState(FacesContext context, Object state)
      Invoked in the "restore view" phase, this initialises this object's members from the values saved previously into the provided state object.

      Parameters:
      state - is an object previously returned by the saveState method of this class.
    • setRendered

      public void setRendered(boolean rendered)
      Specified by:
      setRendered in class UIComponent
    • setRendererType

      public void setRendererType(String rendererType)
      Specified by:
      setRendererType in class UIComponent