int numNonNulls = 8;
for(int i = 0; i < numNonNulls; i++) {
List<String> filledList = new ArrayList<String>(2);
filledList.add("SomeText");
filledList.add("SomeMoreText" + i);
writer.addRow(new StringListWithId(i, filledList));
}
for(int j = 0; j < numNulls; j++) {
writer.addRow(new StringListWithId(numNonNulls+j, emptyList));
}
writer.close();
// Prepare to read back the data