// aggregate drawing records.
// The subrange [19, 388] is expected to be replaced with a EscherAggregate object
DrawingManager2 drawingManager = iworkbook.findDrawingGroup();
int loc = isheet.aggregateDrawingRecords(drawingManager, false);
EscherAggregate agg = (EscherAggregate) records.get(loc);
assertEquals("wrong size of the aggregated sheet records stream", 25, records.size());
assertTrue(
"records.get(18) is expected to be RowRecordsAggregate but was " + records.get(18).getClass().getSimpleName(),
records.get(18) instanceof RowRecordsAggregate);
assertTrue("records.get(19) is expected to be EscherAggregate but was " + records.get(19).getClass().getSimpleName(),
records.get(19) instanceof EscherAggregate);
assertTrue("records.get(20) is expected to be Window2 but was " + records.get(20).getClass().getSimpleName(),
records.get(20) instanceof WindowTwoRecord);
byte[] dgBytesAfterSave = agg.serialize();
assertEquals("different size of drawing data before and after save", dgBytes.length, dgBytesAfterSave.length);
assertTrue("drawing data before and after save is different", Arrays.equals(dgBytes, dgBytesAfterSave));
}