Created attachment 38740 [details]
diff orig/SheetUtil.java new/SheetUtil.java

Most of cases, merged Cells have one to be non-empty Cell. But in that cases, getCellWithMerges() return not non-empty Cell but empty Cell. Certainly, empty Cell is not null. But it is not correct result of getCellWithMerges() for SheetUtil.

In my test results, getCell(sheet, rowIx, colIx) doesn't return null when merged some Cell is empty. getCell(sheet, rowIx, colIx) returns empty Cell that is not null. I test on Microsoft Excel file.

getCellWithMerges() is not correct. It must fix.