private Map<Album, Map<ImageType, Resource>> collectAlbumTargets(
Library library, final ResourceLocator resourceLocator, Collection<Album> changedAlbums) {
Map<Album, Map<ImageType, Resource>> result = new HashMap<>();
for (Album album : library.getAlbums()) {
Resource artworkAssetResource = album.artworkAssetResource();
if (artworkAssetResource != null) {
Map<ImageType, Resource> targets = new HashMap<ImageType, Resource>();
for (ImageType type : ImageType.values()) {
String imagePath = resourceLocator.getAlbumImagePath(album, type);
if (imagePath != null) {
Resource resource = resourceLocator.getResource(imagePath);
try {
if (changedAlbums.contains(album) || !resource.exists()) {
resource.getParent().mkdirs();
targets.put(type, resource);
}
} catch (IOException e) {
LOGGER.warning("Could not write image file: " + resource.getPath().toAbsolutePath());
}
}
}
if (!targets.isEmpty()) {
result.put(album, targets);
}
}
}
return result;
}