While Reading the data from Excel file with extension xlsx using apache poi it takes long time

问题

While reading the excel file with extension xlsx using apache poi it takes the long time for identifying the extension. Can you please help why it takes the long time?

if (file.getExcelFile().getOriginalFilename().endsWith("xls"))
    {
    workbook = new HSSFWorkbook(file.getExcelFile().getInputStream());
    } else if (file.getExcelFile().getOriginalFilename().endsWith("xlsx"))
    {
    workbook = new XSSFWorkbook(file.getExcelFile().getInputStream());
    } else {
    throw new IllegalArgumentException("Received file does not have a standard excel extension.");
    }

回答1:

Promoting a comment to an answer - don't try to do this yourself, Apache POI has built-in code for doing this for you!

You should use WorkbookFactory.create(File) to do it, eg just

workbook = WorkbookFactory.create(file.getExcelFile());

As explained in the Apache POI docs, use a File directly in preference to an InputStream for quicker and lower memory processing

来源：https://stackoverflow.com/questions/39567127/while-reading-the-data-from-excel-file-with-extension-xlsx-using-apache-poi-it-t