public MediaCopy addCopy(Media media) {
lastCopyId += 1;
MediaCopy mediaCopy = new MediaCopy(media, "" + lastCopyId);
String mediaId = media.getId();
List copies = (List) mediaCopies.get(mediaId);
if (copies == null) {
copies = new LinkedList();
mediaCopies.put(mediaId, copies);
}
copies.add(mediaCopy);
return mediaCopy;
}
public Map findAllISBNsAndTitles() {
List isbns = findAllKeysForValuesOfType(Book.class);
Map map = new HashMap();
for (Iterator iter = isbns.iterator(); iter.hasNext(); ) {
String isbn = (String) iter.next();
List copies = (List) mediaCopies.get(isbn);
if (copies.size() > 0) {
String title = ((MediaCopy) copies.get(0)).getMedia().getTitle();
map.put(isbn, title);
}
}
return map;
}