row = new ArrayList<Writable>(numColumns);
// set each value in rowBase to the writable that corresponds with its PrimitiveObjectInspector
for (int c = 0; c < numColumns; c++) {
PrimitiveObjectInspector poi = (PrimitiveObjectInspector)columnOIs.get(c);
Writable writable;
try {
writable = (Writable)poi.getPrimitiveWritableClass().newInstance();
} catch (InstantiationException e) {
throw new SerDeException("Error creating Writable from ObjectInspector", e);
} catch (IllegalAccessException e) {
throw new SerDeException("Error creating Writable from ObjectInspector", e);
}