after write(), no dispose():       1 temp file(s) left: [poi-sxssf-sheet2787588911680201252.xml]
after close() only:                0 temp file(s) left
after dispose():                   0 temp file(s) left

temp file size after writing 50,000 rows (9 columns), before dispose():
  compressTempFiles=false: 24,339,585 bytes
  compressTempFiles=true:  2,974,461 bytes