com.vaadin.flow.server.

Class StaticFileServer

  • All Implemented Interfaces:

    StaticFileHandler, Serializable


    public class StaticFileServer
extends Object
implements StaticFileHandler

    Handles sending of resources from the WAR root (web content) or META-INF/resources in the case that VaadinServlet is mapped using "/*".

    This class is primarily meant to be used during developing time. For a production mode site you should consider serving static resources directly from the servlet (using a default servlet if such exists) or through a stand alone static file server.

    Since:

    1.0

    Author:

    Vaadin Ltd

    See Also:

    Serialized Form

    • Method Summary

      All Methods
      Modifier and Type Method and Description
      protected boolean browserHasNewestVersion(HttpServletRequest request, long resourceLastModifiedTimestamp)

      Checks if the browser has an up to date cached version of requested resource using the "If-Modified-Since" header.
      protected int getCacheTime(String filenameWithPath)

      Calculates the cache lifetime for the given filename in seconds.
      boolean isStaticResourceRequest(HttpServletRequest request)

      Checks if a static resource can be found for the requested path.
      boolean serveStaticResource(HttpServletRequest request, HttpServletResponse response)

      Serves a static resource for the requested path if a resource can be found.
      protected void writeCacheHeaders(String filenameWithPath, HttpServletResponse response)

      Writes cache headers for the file into the response.
      protected long writeModificationTimestamp(URL resourceUrl, HttpServletRequest request, HttpServletResponse response)

      Writes the modification timestamp info for the file into the response.

    • Constructor Detail

      • StaticFileServer

        public StaticFileServer(VaadinServletService servletService)

        Constructs a file server.

        Parameters:

        servletService - servlet service for the deployment, not null

    • Method Detail

      • isStaticResourceRequest

        public boolean isStaticResourceRequest(HttpServletRequest request)

        Description copied from interface: StaticFileHandler

        Checks if a static resource can be found for the requested path.

        Specified by:

        isStaticResourceRequest in interface StaticFileHandler

        Parameters:

        request - the request to check

        Returns:

        true if a static resource exists and can be sent as a response to this request, false otherwise

      • serveStaticResource

        public boolean serveStaticResource(HttpServletRequest request,
                                   HttpServletResponse response)
                            throws IOException

        Description copied from interface: StaticFileHandler

        Serves a static resource for the requested path if a resource can be found.

        Specified by:

        serveStaticResource in interface StaticFileHandler

        Parameters:

        request - the request object to read from

        response - the response object to write to

        Returns:

        true if a file was served and the request has been handled, false otherwise.

        Throws:

        IOException - if the underlying servlet container reports an exception

      • writeModificationTimestamp

        protected long writeModificationTimestamp(URL resourceUrl,
                                          HttpServletRequest request,
                                          HttpServletResponse response)

        Writes the modification timestamp info for the file into the response.

        Parameters:

        resourceUrl - the internal URL of the file

        request - the request object

        response - the response object

        Returns:

        the written timestamp or -1 if no timestamp was written

      • writeCacheHeaders

        protected void writeCacheHeaders(String filenameWithPath,
                                 HttpServletResponse response)

        Writes cache headers for the file into the response.

        Parameters:

        filenameWithPath - the name and path of the file being sent

        response - the response object

      • getCacheTime

        protected int getCacheTime(String filenameWithPath)

        Calculates the cache lifetime for the given filename in seconds.

        By default filenames containing ".nocache." return 0, filenames containing ".cache." return one year and all other files return 1 hour.

        Parameters:

        filenameWithPath - the name of the file being sent

        Returns:

        cache lifetime for the given filename in seconds

      • browserHasNewestVersion

        protected boolean browserHasNewestVersion(HttpServletRequest request,
                                          long resourceLastModifiedTimestamp)

        Checks if the browser has an up to date cached version of requested resource using the "If-Modified-Since" header.

        Parameters:

        request - The HttpServletRequest from the browser.

        resourceLastModifiedTimestamp - The timestamp when the resource was last modified. -1 if the last modification time is unknown.

        Returns:

        true if the If-Modified-Since header tells the cached version in the browser is up to date, false otherwise