final int TUPLE_COUNT = 20000;
List<ColumnMetadata> cdlist = new ArrayList<ColumnMetadata>();
cdlist.add(new SimpleColumnMetadata("A", TupleTypes._INT, 0, 0, 11));
cdlist.add(new SimpleColumnMetadata("B", TupleTypes._INT, 0, 0, 11));
cdlist.add(new SimpleColumnMetadata("C", TupleTypes._INT, 0, 0, 11));
TupleMetadata metadata = new SimpleTupleMetadata(cdlist);
TestBlockReader input = new TestBlockReader(TUPLE_COUNT);
input.setTupleFactory(new SimpleTupleFactory());
input.setTupleMetadata(metadata);
SortActivity activity = new SortActivity();
activity.addInput("data", input);