Package com.sun.faces.application.resource

Class ResourceHelper

    • Constructor Detail

      • ResourceHelper

        public ResourceHelper()

    • Method Detail

      • getBaseResourcePath

        public abstract String getBaseResourcePath()
        Returns:
        the base path in which resources will be stored

      • getBaseContractsPath

        public abstract String getBaseContractsPath()

      • getBasePath

        protected String getBasePath​(String contract)

      • getInputStream

        public InputStream getInputStream​(ResourceInfo toStream,
                                  FacesContext ctx)
                           throws IOException

        If the resource is compressable, return an InputStream to read the compressed content, otherwise, call getNonCompressedInputStream(ResourceInfo, jakarta.faces.context.FacesContext) to return the content of the original resource.

        Implementation Note: If any exception occurs trying to return a stream to the compressed content, log the exception, and instead try to return a stream to the original content.

        Parameters:
        toStream - the resource to obtain an InputStream to
        ctx - the FacesContext for the current request
        Returns:
        an InputStream to the resource, or null if no resource is found
        Throws:
        IOException - if an error occurs obtaining the stream

      • getURL

        public abstract URL getURL​(ResourceInfo resource,
                           FacesContext ctx)
        Parameters:
        resource - the resource to obtain a URL reference to
        ctx - the FacesContext for the current request
        Returns:
        a URL to the specified resource, otherwise null if no resource is found

      • findLibrary

        public abstract LibraryInfo findLibrary​(String libraryName,
                                        String localePrefix,
                                        String contract,
                                        FacesContext ctx)
        Search for the specified library/localPrefix combination in an implementation dependent manner.
        Parameters:
        libraryName - the name of the library
        localePrefix - the logicial identifier for a locale specific library. if no localePrefix is configured, pass null
        contract - the name of the contract
        ctx - the FacesContext for the current request @return a LibraryInfo if a matching library based off the inputs can be found, otherwise returns null
        Returns:
        library info

      • findResource

        public abstract ResourceInfo findResource​(LibraryInfo library,
                                          String resourceName,
                                          String localePrefix,
                                          boolean compressable,
                                          FacesContext ctx)

        Search for the specified resource based in the library/localePrefix/resourceName combination in an implementation dependent manner.

        If the resource is found, and is compressable, call handleCompression(com.sun.faces.application.resource.ClientResourceInfo) to compress the content.

        Parameters:
        library - the library this resource should be a part of. If the the resource that is being searched for isn't part of a library, then pass null
        resourceName - the name of the resource that is being searched for
        localePrefix - the logicial identifier for a locale specific library. if no localePrefix is configured, pass null
        compressable - true if the resource can be compressed
        ctx - the FacesContext for the current request
        Returns:
        a ResourceInfo if a matching resource based off the inputs can be found, otherwise returns null

      • getLastModified

        public long getLastModified​(ResourceInfo resource,
                            FacesContext ctx)

        The default implementation of this method will call through to getURL(ResourceInfo, jakarta.faces.context.FacesContext) and leverage the URL to obtain the date information of the resource and return the value of URLConnection.getLastModified()

        Parameters:
        resource - the resource in question
        ctx - the FacesContext for the current request
        Returns:
        the date of the resource in milliseconds (since epoch), or 0 if the date cannot be determined

      • getVersion

        protected VersionInfo getVersion​(Collection<String> resourcePaths,
                                 boolean isResource)

        Given a collection of path names: 

           1.1, scripts, images, 1.2

        this method will pick out the directories that represent a library or resource version and return the latest version found, if any.

        Parameters:
        resourcePaths - a collection of paths (consisting of single path elements)
        isResource - true if the version being looked up is for a reource, otherwise, pass false if the version is a library version
        Returns:
        the latest version or if no version can be detected, otherwise this method returns null

      • compressContent

        protected boolean compressContent​(ClientResourceInfo info)
                           throws IOException
        Utility method to compress the content of the original resource to the temporary directory specified by ClientResourceInfo.getCompressedPath().
        Parameters:
        info - the resource to be compressed
        Returns:
        true if compression succeeded and the compressed result is smaller than the original content, otherwise false
        Throws:
        IOException - if any error occur reading/writing

      • clientAcceptsCompression

        protected boolean clientAcceptsCompression​(FacesContext ctx)

        This method attempt to verify that the user agent can accept a gzip encoded response by interrogating the Accept-Encoding requester header. If it is determined safe to send a gzip encoded response, send the Content-Encoding header with a value of gzip.

        See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616, sec. 14 for details on the accept-encoding header.

        Implementation Note: It is safe to cast to a HttpServletResponse as this method will only be called when handling a resource request. Resource serving is outside of the Faces and Portlet lifecycle.

        Parameters:
        ctx - the FacesContext for the current request
        Returns:
        true if compressed content can be sent to the client, otherwise false

      • handleCompression

        protected ClientResourceInfo handleCompression​(ClientResourceInfo resource)

        Utility method to peform the necessary actions to compress content.

        Implmentation Note: If an exception occurs while compressing the content, log the IOException and rebuilt the ResourceInfo as non-compressable.

        Parameters:
        resource - the resource to compression
        Returns:
        the ResourceInfo after compression is complete. If compression was successful, this should be the same instance. If compression was not successful, it will be a different instance than what was passed.

      • resourceSupportsEL

        protected boolean resourceSupportsEL​(String resourceName,
                                     String libraryName,
                                     FacesContext ctx)

      • trimLeadingSlash

        protected String trimLeadingSlash​(String s)
        Parameters:
        s - input String
        Returns:
        the String without a leading slash if it has one.