High memory usage in SpudSoft Xlsx Emitter

[speckyspooky]

Discussed in #1318

^{Originally posted by redkark June 8, 2023}
I observe high memory usage when using Spudsoft Emitter while generate XLSX output for larger data volumes. I am using the BIRT runtime v4.12 in my Java code to generate the reports. I looked at certain posts where it was suggested to use the ExcelEmitter.Extract in the render options to instruct the spudsoft emitter to use the "streaming" SXSSFWorkbook from Apache POI. However it did not have desired effect. Upon looking at the code for XslxEmitter, I noticed it uses the XSSFWorkbook with no option provided to switch to the SXSSFWorkbook. Would like to know if it is possible to configure spudsoft emitter to make use of the SXSSSFWorkbook, via the render options or other mechanisms?

[speckyspooky]

To have the miniumum of impact to the main project, we could check whether an additonal ExcelEmitter-option would be possible like "ExcelEmitter.StreamingXlsx" as boolean to setup the xlsx-streaming option.

The important thing is that the usage of XSSF and SXSSF isn't the same so the default would be the current handling with XSSF without streaming. The streaming must beactivated with ExcelEmitter.StreamingXlsx = "true".

Apache POI reference:
https://poi.apache.org/components/spreadsheet/

Apache POI details:
https://poi.apache.org/components/spreadsheet/how-to.html#sxssf

[speckyspooky]

With the latest built of 4.14-snapshot the new emitter-option is available.