+ return new ArrayList<Image>(images.values());
+ }
+
+ /**
+ * Adds the given image to this album.
+ *
+ * @param image
+ * The image to add
+ */
+ public void addImage(Image image) {
+ Validation.begin().isNotNull("Image", image).check().isNotNull("Image Owner", image.getSone()).check().isEqual("Image Owner", image.getSone(), sone).check();
+ if (image.getAlbum() != null) {
+ image.getAlbum().removeImage(image);
+ }
+ image.setAlbum(this);
+ if (images.isEmpty()) {
+ albumImage = image.getId();
+ }
+ if (!images.containsKey(image.getId())) {
+ images.put(image.getId(), image);
+ }
+ }
+
+ /**
+ * Removes the given image from this album.
+ *
+ * @param image
+ * The image to remove
+ */
+ public void removeImage(Image image) {
+ Validation.begin().isNotNull("Image", image).check().isEqual("Image Owner", image.getSone(), sone).check();
+ images.remove(image);
+ if (image.getId().equals(albumImage)) {
+ if (images.isEmpty()) {
+ albumImage = null;
+ } else {
+ albumImage = images.values().iterator().next().getId();
+ }
+ }
+ }
+
+ /**
+ * Returns the album image of this album, or {@code null} if no album image
+ * has been set.
+ *
+ * @return The image to show when this album is listed
+ */
+ public Image getAlbumImage() {
+ if (albumImage == null) {
+ return null;
+ }
+ return images.get(albumImage);
+ }
+
+ /**
+ * Sets the ID of the album image.
+ *
+ * @param id
+ * The ID of the album image
+ * @return This album
+ */
+ public Album setAlbumImage(String id) {
+ this.albumImage = id;
+ return this;
+ }
+
+ /**
+ * Returns whether this album contains any other albums or images.
+ *
+ * @return {@code true} if this album is empty, {@code false} otherwise
+ */
+ public boolean isEmpty() {
+ return albums.isEmpty() && images.isEmpty();
+ }
+
+ /**
+ * Returns the parent album of this album.
+ *
+ * @return The parent album of this album, or {@code null} if this album
+ * does not have a parent
+ */
+ public Album getParent() {
+ return parent;
+ }
+
+ /**
+ * Sets the parent album of this album.
+ *
+ * @param parent
+ * The new parent album of this album
+ * @return This album
+ */
+ protected Album setParent(Album parent) {
+ Validation.begin().isNotNull("Album Parent", parent).check();
+ this.parent = parent;
+ return this;
+ }
+
+ /**
+ * Removes the parent album of this album.
+ *
+ * @return This album
+ */
+ protected Album removeParent() {
+ this.parent = null;
+ return this;