/**
* Attempts to retrieve the specified tree rule from storage.
*
* @param tsdb The TSDB to use for storage access
* @param tree_id ID of the tree the rule belongs to
* @param level Level where the rule resides
* @param order Order where the rule resides
* @return A TreeRule object if found, null if it does not exist
* @throws HBaseException if there was an issue
* @throws IllegalArgumentException if the one of the required parameters was missing
* @throws JSONException if the object could not be serialized
*/
public static Deferred<TreeRule> fetchRule(
final TSDB tsdb, final int tree_id, final int level, final int order) {
if (tree_id < 1 || tree_id > 65535) {
throw new IllegalArgumentException("Invalid Tree ID");
}
if (level < 0) {
throw new IllegalArgumentException("Invalid rule level");
}
if (order < 0) {
throw new IllegalArgumentException("Invalid rule order");
}
// fetch the whole row
final GetRequest get = new GetRequest(tsdb.treeTable(), Tree.idToBytes(tree_id));
get.family(Tree.TREE_FAMILY());
get.qualifier(getQualifier(level, order));
/** Called after fetching to parse the results */
final class FetchCB implements Callback<Deferred<TreeRule>, ArrayList<KeyValue>> {
@Override
public Deferred<TreeRule> call(final ArrayList<KeyValue> row) {
if (row == null || row.isEmpty()) {
return Deferred.fromResult(null);
}
return Deferred.fromResult(parseFromStorage(row.get(0)));
}
}
return tsdb.getClient().get(get).addCallbackDeferring(new FetchCB());
}
/**
* Attempts to delete all rules belonging to the given tree.
*
* @param tsdb The TSDB to use for storage access
* @param tree_id ID of the tree the rules belongs to
* @return A deferred to wait on for completion. The value has no meaning and may be null.
* @throws HBaseException if there was an issue
* @throws IllegalArgumentException if the one of the required parameters was missing
*/
public static Deferred<Object> deleteAllRules(final TSDB tsdb, final int tree_id) {
if (tree_id < 1 || tree_id > 65535) {
throw new IllegalArgumentException("Invalid Tree ID");
}
// fetch the whole row
final GetRequest get = new GetRequest(tsdb.treeTable(), Tree.idToBytes(tree_id));
get.family(Tree.TREE_FAMILY());
/**
* Called after fetching the requested row. If the row is empty, we just return, otherwise we
* compile a list of qualifiers to delete and submit a single delete request to storage.
*/
final class GetCB implements Callback<Deferred<Object>, ArrayList<KeyValue>> {
@Override
public Deferred<Object> call(final ArrayList<KeyValue> row) throws Exception {
if (row == null || row.isEmpty()) {
return Deferred.fromResult(null);
}
final ArrayList<byte[]> qualifiers = new ArrayList<byte[]>(row.size());
for (KeyValue column : row) {
if (column.qualifier().length > RULE_PREFIX.length
&& Bytes.memcmp(RULE_PREFIX, column.qualifier(), 0, RULE_PREFIX.length) == 0) {
qualifiers.add(column.qualifier());
}
}
final DeleteRequest delete =
new DeleteRequest(
tsdb.treeTable(),
Tree.idToBytes(tree_id),
Tree.TREE_FAMILY(),
qualifiers.toArray(new byte[qualifiers.size()][]));
return tsdb.getClient().delete(delete);
}
}
return tsdb.getClient().get(get).addCallbackDeferring(new GetCB());
}