code: public static <E extends Exception> void flatOp(final short[][] a, Try.Consumer<short[], E> op) throws E {
          if (N.isNullOrEmpty(a)) {
              return;
          }
  
          final short[] tmp = flatten(a);
  
          op.accept(tmp);
  
          int idx = 0;
  
          for (short[] e : a) {
              if (N.notNullOrEmpty(e)) {
                  N.copy(tmp, idx, e, 0, e.length);
                  idx += e.length;
              }
          }
      }
docs: flatten -> execute {@code op} -> set values back.
  <pre>
  <code>
  f.flatOp(a, t -> N.sort(t));
  </code>
  </pre>
  
  @param a
  @param op
  @throws E