/**
* Returns a JSON object containing only the specified fields from the provided resource. If the
* list of fields is empty then the resource is returned unchanged.
*
* <p><b>NOTE:</b> this method only performs a shallow copy of extracted fields, so changes to the
* filtered resource may impact the original resource, and vice-versa.
*
* @param resource The resource whose fields are to be filtered.
* @param fields The list of fields to be extracted.
* @return The filtered resource.
*/
public static Resource filterResource(
final Resource resource, final Collection<JsonPointer> fields) {
final JsonValue unfiltered = resource.getContent();
final JsonValue filtered = filterResource(unfiltered, fields);
if (filtered == unfiltered) {
return resource; // Unchanged.
} else {
return new Resource(resource.getId(), resource.getRevision(), filtered);
}
}
/**
* TODO: Description.
*
* @throws SynchronizationException TODO.
*/
void create() throws SynchronizationException {
_id = UUID.randomUUID().toString(); // client-assigned identifier
JsonValue jv = toJsonValue();
try {
CreateRequest r = Requests.newCreateRequest(linkId(null), _id, jv);
Resource resource =
mapping
.getService()
.getConnectionFactory()
.getConnection()
.create(mapping.getService().getServerContext(), r);
this._id = resource.getId();
this._rev = resource.getRevision();
this.initialized = true;
} catch (ResourceException ose) {
LOGGER.debug("Failed to create link", ose);
throw new SynchronizationException(ose);
}
}
/**
* Update a link.
*
* @throws SynchronizationException if updating link fails
*/
void update() throws SynchronizationException {
if (_id == null) {
throw new SynchronizationException("Attempt to update non-existent link");
}
JsonValue jv = toJsonValue();
try {
UpdateRequest r = Requests.newUpdateRequest(linkId(_id), jv);
r.setRevision(_rev);
Resource resource =
mapping
.getService()
.getConnectionFactory()
.getConnection()
.update(mapping.getService().getServerContext(), r);
_rev = resource.getRevision();
} catch (ResourceException ose) {
LOGGER.warn("Failed to update link", ose);
throw new SynchronizationException(ose);
}
}