/** Suck up tuples from the source file. */
private Tuple readNextTuple(DataInputStream dis, int slotId) throws NoSuchElementException {
// if associated bit is not set, read forward to the next tuple, and
// return null.
if (!isSlotUsed(slotId)) {
for (int i = 0; i < td.getSize(); i++) {
try {
dis.readByte();
} catch (IOException e) {
throw new NoSuchElementException("error reading empty tuple");
}
}
return null;
}
// read fields in the tuple
Tuple t = new Tuple(td);
RecordId rid = new RecordId(pid, slotId);
t.setRecordId(rid);
try {
for (int j = 0; j < td.numFields(); j++) {
Field f = td.getFieldType(j).parse(dis);
t.setField(j, f);
}
} catch (java.text.ParseException e) {
e.printStackTrace();
throw new NoSuchElementException("parsing error!");
}
return t;
}
