public <SN,N,V> Mutator<K> addSubDelete(K key, String cf, HSuperColumn<SN,N,V> sc, long clock) {
SlicePredicate pred = new SlicePredicate();
Deletion d = new Deletion().setTimestamp(clock);
if ( sc.getColumns() != null ) {
for (HColumn<N, V> col : sc.getColumns()) {
pred.addToColumn_names(col.getNameSerializer().toByteBuffer(col.getName()));
}
d.setPredicate(pred);
}
d.setSuper_column(sc.getNameByteBuffer());
getPendingMutations().addDeletion(key, Arrays.asList(cf), d);