The intent of this document is to outline some of the known limitations of the POI HSSF API's. It is not intended to be complete list of every bug or missing feature of HSSF, rather it's purpose is to provide a broad feel for some of the functionality that is missing or broken.

• Charts
  
  You can not currently create charts. You can however create a chart in Excel, modify the chart data values using HSSF and write a new spreadsheet out. This is possible because POI attempts to keep existing records intact as far as possible.
  
  
• Rich Text
  
  HSSF does not support rich text cells. Rich text cells are cells that have multiple fonts and styles in the once cell. Any attempt to read a spreadsheet that has rich text cells will throw an exception. This feature may be supported in the future but it is not currently planned. Patches are welcome.
  
  
• Outlines
  
  It is not yet possible to create outlines. Reading a spreadsheet with outlines may work correctly but has not been tested. Write support for outlines may be added in the future but it is not currently planned. Patches are welcome.
  
  
• Macros
  
  Macros can not be created. However, reading and re-writing files containing macros will safely preserve the macros.
  
  
• Pivot Tables
  
  Generating pivot tables is not supported. It has been reported that files containing pivot tables can be read and re-written safely.