Hello, When I try to shift rows by calling HSSFSheet#shiftRows(),that contains BLANK (the RowRecord is not exist at the row number) row,the method throws NullPointerException. I feel , in such case users expect, not throws any Exceptions, but simply remove the target row's record from the sheet.
Created attachment 4017 [details] PATCH for HSSFSheet#shiftRows()
Created attachment 4157 [details] Testcase for this problem.
Applied patch and moved the other test case for shifts into the test case file applied. Added the copyright at the top and ran through everything. Put Toshiaki Kamoshida as author in the test case.