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excelxlsapache-poixlsx

Apache POI for Excel: Setting the cell type to "text" for an entire column


I need to generate an .xls (Excel) file, using the Java library Apache POI for spreadsheets.

The file will contain a list of phone numbers in column A, formatted as "0221...." or "+49221..." - so Excel by default interprets them as numeric cells. This is bad, because the leading 0 or + will get trimmed.

To solve the problem, I can use cell.setCellType(Cell.CELL_TYPE_STRING), which works fine, but only for the specific cells I set this for.

How can I apply this setting for the entire column (i.e. even for all the remaining cells, where the user will enter additional phone numbers)?

In Excel, this is possible: Selecting the entire column, and apply the cell type (the setting survives saving/loading the file.)

But I can't find the correct method for POI.

  • First I assumed, it should be something like sheet.setDefaultCellType(int colNum). But I can't find anything like this (probably I'm just blind? There are lots of similar methods in the library for applying text styles like "align center" etc.)
  • Then I thought: Maybe it can only be applied to a NamedRange or something similar, but I haven't managed to work out how this works...

Solution

  • Will this help?

    By creating a data format with the @ symbol and using that in a CellStyle object that is then passed to the setDefaultColumnStyle() method, it was possible to set the default data type of the column to, in this case, text. I have not experiemented further but do suspect it would be possible to do something similar with other style objects to set the default type to numeric or even a customised format such as currency.