formily | 📱🚀 🧩 Cross Device & High Performance Normal Form | Form library

In current Apache poi 5.0.0 SheetConditionalFormatting does not have a method to create a ConditionalFormattingRule for top 10. But it has SheetConditionalFormatting.createConditionalFormattingColorScaleRule(). So your linked excample which uses underlying org.openxmlformats.schemas.spreadsheetml.x2006.main.* classes for creating color scale rule is outdated.

But top 10 rule settings are more complex than color scale rule settings. For color scale rule all settings are in sheet's CTConditionalFormatting. For top 10 rule a fill pattern formatting needs to be used. That pattern formatting links to the style part of the workbook.

So best way would be creating a XSSFConditionalFormattingRule for top 10 which sets type STCfType.TOP_10 and rank. This ConditionalFormattingRule already provides a method to create pattern formatting.

Unfortunately constructor of XSSFConditionalFormattingRule is not public as well as the method to get CTCfRule. So reflection needs to be used.

Following complete example provides XSSFConditionalFormattingRule createConditionalFormattingRuleTop10(XSSFSheetConditionalFormatting sheetCF, int rank) to create a XSSFConditionalFormattingRule for top 10 given a special rank. All other stuff is like the default stuff for creating conditional formatting as described in Busy Developers' Guide to HSSF and XSSF Features - Conditional Formatting.