Package javax.faces.view

Class ViewDeclarationLanguage

  • Direct Known Subclasses:
    ViewDeclarationLanguageWrapper

    public abstract class ViewDeclarationLanguage
extends java.lang.Object

    The contract that a view declaration language must implement to interact with the JSF runtime. An implementation of this class must be thread-safe.

    Instances of this class are application scoped and must be obtained from the ViewDeclarationLanguageFactory.

    Since:
    2.0

    • Field Detail

      • JSP_VIEW_DECLARATION_LANGUAGE_ID

        public static final java.lang.String JSP_VIEW_DECLARATION_LANGUAGE_ID

        Identifier for the JSP view declaration language.

        Since:
        2.1
        See Also:
        Constant Field Values

      • FACELETS_VIEW_DECLARATION_LANGUAGE_ID

        public static final java.lang.String FACELETS_VIEW_DECLARATION_LANGUAGE_ID

        Identifier for the Facelets view declaration language.

        Since:
        2.1
        See Also:
        Constant Field Values

    • Constructor Detail

      • ViewDeclarationLanguage

        public ViewDeclarationLanguage​()

    • Method Detail

      • getComponentMetadata

        public abstract java.beans.BeanInfo getComponentMetadata​(FacesContext context,
                                                         Resource componentResource)

        Return a reference to the component metadata for the composite component represented by the argument componentResource, or null if the metadata cannot be found. See section JSF.7.7.2 for the specification of the default implementation. JSP implementations must throw UnsupportedOperationException.

        Parameters:
        context - The FacesContext for this request.
        componentResource - The Resource that represents the component.
        Throws:
        java.lang.NullPointerException - if any of the arguments are null.
        FacesException - if there is an error in obtaining the metadata
        java.lang.UnsupportedOperationException - if this is a JSP VDL implementation.
        Since:
        2.0

      • getViewMetadata

        public abstract ViewMetadata getViewMetadata​(FacesContext context,
                                             java.lang.String viewId)

        Return a reference to the view metadata for the view represented by the argument viewId, or null if the metadata cannot be found. See section JSF.7.7.2 for the specification of the default implementation. Facelets for JSF 2 implementation must return non-null. JSP implementations must return null.

        Parameters:
        context - The FacesContext for this request.
        viewId - the view id from whith to extract the metadata
        Throws:
        java.lang.NullPointerException - if any of the arguments are null.
        FacesException - if there is an error in obtaining the metadata
        Since:
        2.0

      • getScriptComponentResource

        public abstract Resource getScriptComponentResource​(FacesContext context,
                                                    Resource componentResource)

        Take implementation specific action to discover a Resource given the argument componentResource. See section JSF.7.7.2 for the specification of the default implementation. JSP implementations must throw UnsupportedOperationException.

        Parameters:
        context - The FacesContext for this request.
        componentResource - The Resource that represents the component.
        Throws:
        java.lang.NullPointerException - if any of the arguments are null.
        FacesException - if there is an error in obtaining the script component resource
        java.lang.UnsupportedOperationException - if this is a JSP VDL implementation.
        Since:
        2.0

      • createView

        public abstract UIViewRoot createView​(FacesContext context,
                                      java.lang.String viewId)

        Create a UIViewRoot from the VDL contained in the artifact referenced by the argument viewId. See section JSF.7.7.2 for the specification of the default implementation.

        Parameters:
        context - the FacesContext for this request.
        viewId - the identifier of an artifact that contains the VDL syntax that describes this view.
        Throws:
        java.lang.NullPointerException - if any of the arguments are null
        Since:
        2.0

      • createComponent

        public UIComponent createComponent​(FacesContext context,
                                   java.lang.String taglibURI,
                                   java.lang.String tagName,
                                   java.util.Map<java.lang.String,java.lang.Object> attributes)

        Create a component given a ViewDeclarationLanguage specific tag library URI and tag name. The runtime must support this method operating for the Facelets VDL. Other kinds of ViewDeclarationLanguage may be supported but are not required to be supported. For backward compatibility with decorated ViewDeclrationLanguage implementations that do not override this method, a default implementation is provided that returns null. However, any implementation that is compliant with the version of the specification in which this method was introduced must implement this method.

        Parameters:
        context - the FacesContext for this request
        taglibURI - the fully qualified tag library URI that contains the component
        tagName - the name of the tag within that library that exposes the component
        attributes - any name=value pairs that would otherwise have been given on the markup that would cause the creation of this component or null if no attributes need be given.
        Throws:
        java.lang.NullPointerException - if context, taglibURI, or tagName are null
        Since:
        2.2

      • restoreView

        public abstract UIViewRoot restoreView​(FacesContext context,
                                       java.lang.String viewId)

        Restore a UIViewRoot from a previously created view. See section JSF.7.7.2 for the specification of the default implementation.

        Parameters:
        context - the FacesContext for this request.
        viewId - the identifier for a previously rendered view.
        Throws:
        java.lang.NullPointerException - if any of the arguments are null

      • retargetAttachedObjects

        public void retargetAttachedObjects​(FacesContext context,
                                    UIComponent topLevelComponent,
                                    java.util.List<AttachedObjectHandler> handlers)

        Assuming the component metadata for argument topLevelComponent has been made available by an earlier call to getComponentMetadata(javax.faces.context.FacesContext, javax.faces.application.Resource), leverage the component metadata for the purpose of re-targeting attached objects from the top level composite component to the individual AttachedObjectTarget instances inside the composite component. This method must be called by the ViewDeclarationLanguage implementation when creating the UIComponent tree when a composite component usage is encountered.

        An algorithm semantically equivalent to the following must be implemented.

        The implementation must support retargeting attached objects from the top level compsite component to targets that are composite and non-composite components.

        An implementation is provided that will throw UnsupportedOperationException. A Faces implementation compliant with version 2.0 and beyond of the specification must override this method.

        Parameters:
        context - the FacesContext for this request.
        topLevelComponent - The UIComponent in the view to which the attached objects must be attached. This UIComponent must have its component metadata already associated and available from via the JavaBeans API.
        Throws:
        java.lang.NullPointerException - if any of the arguments are null.
        Since:
        2.0

      • retargetMethodExpressions

        public void retargetMethodExpressions​(FacesContext context,
                                      UIComponent topLevelComponent)

        Assuming the component metadata for argument topLevelComponent has been made available by an earlier call to getComponentMetadata(javax.faces.context.FacesContext, javax.faces.application.Resource), leverage the component metadata for the purpose of re-targeting any method expressions from the top level component to the appropriate inner component. For each attribute that is a MethodExpression (as indicated by the presence of a "method-signature" attribute and the absence of a "type" attribute), the following action must be taken:

        • Get the value of the targets attribute. If the value is a ValueExpression evaluate it. If there is no targets attribute, let the name of the metadata element be the evaluated value of the targets attribute.

        • Interpret targets as a space (not tab) separated list of ids. For each entry in the list:

          • Find the inner component of the topLevelComponent with the id equal to the current list entry. For discussion, this component is called target. If not found, log and error and continue to the next attribute.

          • For discussion the declared name of the attribute is called name.

          • In the attributes map of the topLevelComponent, look up the entry under the key name. Assume the result is a ValueExpression. For discussion, this is attributeValueExpression. If not found, log an error and continue to the next attribute.

          • If name is equal to the string "action", or "actionListener" without the quotes, assume target is an ActionSource2.

          • If name is equal to the string "validator", or "valueChangeListener" without the quotes, assume target is an EditableValueHolder.

          • Call getExpressionString() on the attributeValueExpression and use that string to create a MethodExpression of the appropriate signature for name.

          • If name is not equal to any of the previously listed strings, call getExpressionString() on the attributeValueExpression and use that string to create a MethodExpression where the signature is created based on the value of the "method-signature" attribute of the <composite:attribute /> tag.

          • Let the resultant MethodExpression be called attributeMethodExpression for discussion.

          • If name is equal to the string "action" without the quotes, call ActionSource2.setActionExpression(javax.el.MethodExpression) on target, passing attributeMethodExpression.

          • If name is equal to the string "actionListener" without the quotes, call ActionSource.addActionListener(javax.faces.event.ActionListener) on target, passing attributeMethodExpression wrapped in a MethodExpressionActionListener.

          • If name is equal to the string "validator" without the quotes, call EditableValueHolder.addValidator(javax.faces.validator.Validator) on target, passing attributeMethodExpression wrapped in a MethodExpressionValidator.

          • If name is equal to the string "valueChangeListener" without the quotes, call EditableValueHolder.addValueChangeListener(javax.faces.event.ValueChangeListener) on target, passing attributeMethodExpression wrapped in a MethodExpressionValueChangeListener.

          • Otherwise, assume that the MethodExpression should be placed in the components attribute set. The runtme must create the MethodExpression instance based on the value of the "method-signature" attribute.

        An implementation is provided that will throw UnsupportedOperationException. A Faces implementation compliant with version 2.0 and beyond of the specification must override this method.

        Parameters:
        context - the FacesContext for this request.
        topLevelComponent - The UIComponent in the view to which the attached objects must be attached. This UIComponent must have its component metadata already associated and available from via the JavaBeans API.
        Throws:
        java.lang.NullPointerException - if context or topLevelComponent is null.
        Since:
        2.0

      • calculateResourceLibraryContracts

        public java.util.List<java.lang.String> calculateResourceLibraryContracts​(FacesContext context,
                                                                          java.lang.String viewId)

        Return the list of resource library contracts that will be made available for use in the view specified by the argument viewId. If no match is found, return an empty list. See section JSF.7.7.2 for the specification of the default implementation. For backward compatibility with prior implementations, an implementation is provided that returns null, but any implementation compliant with the version of the specification in which this method was introduced must implement it as specified in JSF.7.7.2.

        Parameters:
        context - the FacesContext for this request
        viewId - the view id for which the applicable resource library contracts should be calculated.
        Since:
        2.2

      • buildView

        public abstract void buildView​(FacesContext context,
                               UIViewRoot root)
                        throws java.io.IOException

        Take any actions specific to this VDL implementation to cause the argument UIViewRoot which must have been created via a call to createView(javax.faces.context.FacesContext, java.lang.String), to be populated with children.

        The Facelets implementation must insure that markup comprising the view must be executed, with the UIComponent instances in the view being encountered in the same depth-first order as in other lifecycle methods defined on UIComponent, and added to the view (but not rendered) during the traversal. The runtime must guarantee that the view must be fully populated before any of the following happen.

        If the root is already populated with children, the view must still be re-built, but care must be taken to ensure that the existing components are correctly paired up with their VDL counterparts in the VDL page. Also, any system events that would normally be generated during the adding or removing of components from the view must be temporarily disabled during the creation of the view and then re-enabled when the view has been built.

        Parameters:
        context - the FacesContext for this request
        root - the UIViewRoot to populate with children using techniques specific to this VDL implementation.
        Throws:
        java.io.IOException

      • getStateManagementStrategy

        public abstract StateManagementStrategy getStateManagementStrategy​(FacesContext context,
                                                                   java.lang.String viewId)

        For implementations that want to control the implementation of state saving and restoring, the StateManagementStrategy allows them to do so. Returning null indicates that the implementation wishes the runtime to handle the state saving and restoring. Implementations that provide the VDL for Facelets for JSF 2.0 and later must return non-null from this method.

        Since:
        2.0

      • getId

        public java.lang.String getId​()

        Returns a non-null String that can be used to identify this view declaration language.

        The default implementation returns the fully qualified class name of the view declaration language implementation. Subclasses may override to provide a more meaningful id.

        Since:
        2.1