Merge pull request #4400 from matthias-ronge/patch-43

Improve Javadoc

Kitodo-FileManagement/src/main/java/org/kitodo/filemanagement/FileMapper.java

@@ -17,12 +17,17 @@
 import org.kitodo.config.KitodoConfig;
 
 /**
- * Class for performing mapping and unmapping of URIs.
+ * Contains functions to turn a relative URI into an absolute one and vice
+ * versa.
+ * 
+ * <p>
+ * The name of this class can be misleading: the mapper contains no mapping and
+ * no entry is added to or removed from a mapping.
  */
 class FileMapper {
 
     /**
-     * Map relative URI to absolute kitodo data directory URI.
+     * Maps a relative URI an absolute URI below the Kitodo data directory.
      *
      * @param uri
      *            relative path
@@ -44,6 +49,23 @@ URI unmapUriFromKitodoDataDirectoryUri(URI uri) {
         return unmapDirectory(uri, KitodoConfig.getKitodoDataDirectory());
     }
 
+    /**
+     * Creates a URI relative to {@code directory} if {@code directory} appears
+     * in the URI string; otherwise the URI is returned unchanged. The relative
+     * URI is generated by trimming the URI string to the part after
+     * {@code directory}.
+     *
+     * <p>
+     * The name of this method is misleading: there is no mapping stored
+     * anywhere, and URI is not unregistered from a mapping. Usually such a
+     * function is called relativize.
+     *
+     * @param uri
+     *            absolute path
+     * @param directory
+     *            Kitodo data directory
+     * @return relative URI path
+     */
     private URI unmapDirectory(URI uri, String directory) {
         String path = uri.toString();
         directory = encodeDirectory(directory);