1. What is Apache POI?


Apache POI (Poor Obfuscation Implementation) is a powerful Java library that provides APIs for manipulating various file formats based on Microsoft's OLE2 Compound Document format. It supports:



Excel Files: .xls (HSSF) and .xlsx (XSSF)

Word Documents: .doc and .docx

PowerPoint Presentations: .ppt and .pptx

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