Incorrectly setting TKey causes NPE (to nobody's surprise)

[David Medinets]

I did this:

TKey tKey = new TKey();
tKey.setRow(row_id.getBytes());


TRange tRange = new TRange();
trange.setStart(tKey);

scan.setRange(tRange);

Iterator iterator = scan.iterator();
iterator.hasNext();

This resulted in an NPE in:

org.apache.accumulo.core.data.Key.rowColumnStringBuilder(Key.java:472)

While I have no real objection to this NPE (my code is clearly
deficient), I wonder if a more cogent error message is possible.
Should there be guard statements somewhere to ensure a valid object?