Package jakarta.faces.application

Class Resource

java.lang.Object
jakarta.faces.application.ViewResource
jakarta.faces.application.Resource
Direct Known Subclasses:
ResourceImpl, ResourceWrapper
public abstract class Resource
extends ViewResource

An instance of Resource is a Java object representation of the artifact that is served up in response to a resource request from the client. Instances of Resource are normally created and initialized via calls to ResourceHandler.createResource(java.lang.String). See the documentation for ResourceHandler for more information.

Since:
2.0

  • Field Details

    • COMPONENT_RESOURCE_KEY

      public static final String COMPONENT_RESOURCE_KEY

      This constant is used as the key in the component attribute map of a composite component to associate the component with its Resource instance. The value for this key is the actual Resource instance.

      See Also:
      Constant Field Values

  • Constructor Details

  • Method Details

    • getContentType

      public String getContentType()

      Return the MIME content-type for this resource.

      Returns:
      the MIME content-type for this resource.

    • setContentType

      public void setContentType​(String contentType)

      Set the MIME content-type for this resource. The default implementation performs no validation on the argument.

      Parameters:
      contentType - the MIME content-type for this resource. The default implementation must accept null as a parameter.

    • getLibraryName

      public String getLibraryName()

      Return the libraryName for this resource. May be null. The libraryName for a resource is an optional String that indicates membership in a "resource library". All resources with the same libraryName belong to the same "resource library". The "resource library" concept allows disambiguating resources that have the same resourceName. See ResourceHandler for more information.

      Returns:
      Return the libraryName for this resource. May be null.

    • setLibraryName

      public void setLibraryName​(String libraryName)

      Set the libraryName for this resource.

      Parameters:
      libraryName - the libraryName for this resource. The default implementation must accept null for the libraryName.

    • getResourceName

      public String getResourceName()

      Return the resourceName for this resource. Will never be null. All Resource instances must have a resourceName.

      Returns:
      Return the resourceName for this resource. Will never be null.

    • setResourceName

      public void setResourceName​(String resourceName)

      Set the resourceName for this resource.

      Parameters:
      resourceName - a non-null String.
      Throws:
      NullPointerException - if argument resourceName is null.

    • getInputStream

      public abstract InputStream getInputStream() throws IOException

      If the current request is a resource request, (that is, ResourceHandler.isResourceRequest(jakarta.faces.context.FacesContext) returns true), return an InputStream containing the bytes of the resource. Otherwise, throw an IOException.

      Returns:
      an InputStream containing the bytes of the resource.

      Any Jakarta Expression Language expressions present in the resource must be evaluated before serving the bytes of the resource. Note that due to browser and server caching, Jakarta Expression Language expressions in a resource file will generally only be evaluated once, when the resource is first served up. Therefore, using Jakarta Expression Language expressions that refer to per-request data is not advisable since this data can become stale.

      Throws:
      IOException - if the current request is not a resource request.

    • getResponseHeaders

      public abstract Map<String,​String> getResponseHeaders()

      Returns a mutable Map<String, String> whose entries will be sent as response headers during ResourceHandler.handleResourceRequest(jakarta.faces.context.FacesContext). The entries in this map must not persist beyond the scope of a single request. Any modifications made to the map after the resource has been served will be ignored by the run-time.

      Returns:
      a mutable Map<String, String> of headers that will be included with the response.

    • getRequestPath

      public abstract String getRequestPath()

      Return a path to this resource such that, when the browser resolves it against the base URI for the view that includes the resource, and issues a GET request to the resultant fully qualified URL, the bytes of the resource are returned in response.

      The default implementation must implement the following algorithm. For discussion, the return result from this method will be called result.

      • Get the context-root for this web application, not ending in slash. For discussion this will be called contextRoot.

      • Discover if the FacesServlet is prefix (path) mapped, extension mapped, or exact mapped (as defined by Servlet.12.2.) and the value of the mapping (including the leading '.' in the case of extension mapping). For discussion, this will be facesServletMapping.

        If exact mapped, result must be the following if and only if the FacesServlet is mapped to the exact URL pattern ResourceHandler.RESOURCE_IDENTIFIER + getResourceName()

        result = contextRoot + ResourceHandler.RESOURCE_IDENTIFIER + getResourceName()

        If exact mapped, and the FacesServlet is not mapped to the exact URL pattern ResourceHandler.RESOURCE_IDENTIFIER + getResourceName() do the following:

        Retrieve the existing mappings of the FacesServlet, e.g. using ServletRegistration.getMappings(), and from those pick any prefix mapping or extension mapping. If no such mapping is found, throw an IllegalStateException. If such mapping is found remove the * character from that mapping, take that as the new facesServletMapping and continue with evaluating this mapping as specified below for if prefix mapped and for if extension mapped

        If prefix mapped, result must be

        result = contextRoot + '/' + facesServletMapping + ResourceHandler.RESOURCE_IDENTIFIER + '/' + getResourceName()

        If extension mapped, result must be

        result = contextRoot + ResourceHandler.RESOURCE_IDENTIFIER + getResourceName() + facesServletMapping

      • Build up a string, called resourceMetaData which is an & separated string of name=value pairs suitable for inclusion in a URL query string.

        If getLibraryName() returns non-null, resourceMetaData must include "ln=" + the return from getLibraryName()

        If there is a localePrefix for this application, as defined in ResourceHandler.LOCALE_PREFIX, resourceMetaData must include "loc=" + the localePrefix.

        If this resource is contained in a resource library contract, resourceMetaData must include "con=" + the name of the resource library contract.

        Append "?" + resourceMetaData to result.

      • Make it portlet safe by passing the result through ViewHandler.getResourceURL(jakarta.faces.context.FacesContext, java.lang.String).

      Returns:
      the path to this resource, intended to be included in the encoded view that is sent to the browser when sending a faces response.

    • getURL

      public abstract URL getURL()

      Return an actual URL instance that refers to this resource instance.

      Specified by:
      getURL in class ViewResource
      Returns:
      Return an actual URL instance that refers to this resource instance.

    • toString

      public String toString()

      Call through to getRequestPath() and return the result.

      Overrides:
      toString in class Object
      Returns:
      Call through to getRequestPath() and return the result.

    • userAgentNeedsUpdate

      public abstract boolean userAgentNeedsUpdate​(FacesContext context)

      Return true if the user-agent requesting this resource needs an update. If the If-Modified-Since HTTP header is available for this request, its value must be consulted, as specified in Section 14.25 of IETF RFC 2616, to determine the result. Returns false if the user-agent does not need an update for this resource.

      Parameters:
      context - the Faces context.
      Returns:
      true or false depending on whether or not the user-agent needs an update of this resource.