@POST
@UnitOfWork
@Path("add_view/{personId}")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public synchronized Person addProfileView(
@PathParam("personId") LongParam personId, Viewer viewer)
throws JsonParseException, JsonMappingException, IOException {
// load person object
Person person = findSafely(personId.get());
LinkedList<Viewer> viewers;
// Pending: make sure the viewer Id exists in db
if (viewer.getId() == personId.get())
throw new BadRequestException("Viewer & viewee id's are same");
if (person.getViewers() != null) {
// de-serialise viewers object to list from json
viewers = mapper.readValue(person.getViewers(), new TypeReference<LinkedList<Viewer>>() {});
// filter invalid/obsolete views
LinkedList<Viewer> tmp = new LinkedList<Viewer>();
for (Viewer vr : viewers) {
// if viewer is valid and not same as current one
if (vr.getId() != viewer.getId() && isValid(vr)) tmp.add(vr);
}
// if max viewers are present; remove last one
if (tmp.size() == maxViewers) tmp.removeLast();
viewers = tmp;
} else {
viewers = new LinkedList<Viewer>();
}
// add new viewer
viewers.addFirst(viewer);
person.setViewers(mapper.writeValueAsString(viewers));
personDAO.update(person);
return person;
}
// if viewer is valid
private boolean isValid(Viewer viewer) {
// view is more than maxTTLms old
if (System.currentTimeMillis() - viewer.getTimestamp() > maxTTLms) return false;
return true;
}