Package org.dspace.app.sitemap

Class AbstractGenerator

java.lang.Object
org.dspace.app.sitemap.AbstractGenerator
Direct Known Subclasses:
HTMLSitemapGenerator, SitemapsOrgGenerator
public abstract class AbstractGenerator extends Object
Base class for creating sitemaps of various kinds. A sitemap consists of one or more files which list significant URLs on a site for search engines to efficiently crawl. Dates of modification may also be included. A sitemap index file that links to each of the sitemap files is also generated. It is this index file that search engines should be directed towards.

Provides most of the required functionality, subclasses need just implement a few methods that specify the "boilerplate" and text for including URLs.

Typical usage: 

   AbstractGenerator g = new FooGenerator(...);
   while (...) {
     g.addURL(url, date);
   }
   g.finish();
Author:
Robert Tansley

  • Field Details

    • fileCount

      protected int fileCount
      Number of files written so far

    • bytesWritten

      protected int bytesWritten
      Number of bytes written to current file

    • urlsWritten

      protected int urlsWritten
      Number of URLs written to current file

    • outputDir

      protected File outputDir
      Directory files are written to

    • currentOutput

      protected PrintStream currentOutput
      Current output

  • Constructor Details

    • AbstractGenerator

      public AbstractGenerator(File outputDirIn)
      Initialize this generator to write to the given directory. This must be called by any subclass constructor.
      Parameters:
      outputDirIn - directory to write sitemap files to

  • Method Details

    • startNewFile

      protected void startNewFile() throws IOException
      Start writing a new sitemap file.
      Throws:
      IOException - if IO error if an error occurs creating the file

    • addURL

      public void addURL(String url, Instant lastMod) throws IOException
      Add the given URL to the sitemap.
      Parameters:
      url - Full URL to add
      lastMod - Date URL was last modified, or null
      Throws:
      IOException - if IO error if an error occurs writing

    • closeCurrentFile

      protected void closeCurrentFile() throws IOException
      Finish with the current sitemap file.
      Throws:
      IOException - if IO error if an error occurs writing

    • finish

      public int finish() throws IOException
      Complete writing sitemap files and write the index files. This is invoked when all calls to addURL(String, Instant) have been completed, and invalidates the generator.
      Returns:
      number of sitemap files written.
      Throws:
      IOException - if IO error if an error occurs writing

    • getURLText

      public abstract String getURLText(String url, Instant lastMod)
      Return marked-up text to be included in a sitemap about a given URL.
      Parameters:
      url - URL to add information about
      lastMod - date URL was last modified, or null if unknown or not applicable
      Returns:
      the mark-up to include

    • getLeadingBoilerPlate

      public abstract String getLeadingBoilerPlate()
      Return the boilerplate at the top of a sitemap file.
      Returns:
      The boilerplate markup.

    • getTrailingBoilerPlate

      public abstract String getTrailingBoilerPlate()
      Return the boilerplate at the end of a sitemap file.
      Returns:
      The boilerplate markup.

    • getMaxSize

      public abstract int getMaxSize()
      Return the maximum size in bytes that an individual sitemap file should be.
      Returns:
      the size in bytes.

    • getMaxURLs

      public abstract int getMaxURLs()
      Return the maximum number of URLs that an individual sitemap file should contain.
      Returns:
      the maximum number of URLs.

    • useCompression

      public abstract boolean useCompression()
      Return whether the written sitemap files and index should be GZIP-compressed.
      Returns:
      true if GZIP compression should be used, false otherwise.

    • getFilename

      public abstract String getFilename(int number)
      Return the filename a sitemap at the given index should be stored at.
      Parameters:
      number - index of the sitemap file (zero is first).
      Returns:
      the filename to write the sitemap to.

    • getIndexFilename

      public abstract String getIndexFilename()
      Get the filename the index should be written to.
      Returns:
      the filename of the index.

    • writeIndex

      public abstract void writeIndex(PrintStream output, int sitemapCount) throws IOException
      Write the index file.
      Parameters:
      output - stream to write the index to
      sitemapCount - number of sitemaps that were generated
      Throws:
      IOException - if IO error if an IO error occurs