private CellSetModel buildTestModel() {
   CellSetModel model = new CellSetModel();
   RowModel row;
   row = new RowModel();
   row.setKey(ROW1);
   row.addCell(new CellModel(COLUMN1, TIMESTAMP1, VALUE1));
   model.addRow(row);
   row = new RowModel();
   row.setKey(ROW2);
   row.addCell(new CellModel(COLUMN2, TIMESTAMP2, VALUE2));
   row.addCell(new CellModel(COLUMN3, TIMESTAMP3, VALUE3));
   model.addRow(row);
   return model;
 }