UnionTreeWriter(int columnId,
ObjectInspector inspector,
StreamFactory writer,
boolean nullable) throws IOException {
super(columnId, inspector, writer, nullable);
UnionObjectInspector insp = (UnionObjectInspector) inspector;
List<ObjectInspector> choices = insp.getObjectInspectors();
childrenWriters = new TreeWriter[choices.size()];
for(int i=0; i < childrenWriters.length; ++i) {
childrenWriters[i] = createTreeWriter(choices.get(i), writer, true);
}
tags =