+ private static final long serialVersionUID = 3526489102725366334L;
+
+ private final HashMap<String, AbstractFile> fileNameToFileMap = new HashMap<>();
+
+ public transient boolean changed;
+
+ /**
+ * Performs cleanup of directory model. In particular removes metadata for
+ * images that no longer exist in the filesystem.
+ */
+ public void cleanup() {
+ final Iterator<AbstractFile> fileIterator = fileNameToFileMap.values()
+ .iterator();