Apache Poi performance issue with WorkbookFactory.

问题:

I am trying to retrieve named ranges from excel file using the apache poi plugin.

The code snippet is as given below.

I see that call WorkbookFactory.create(excelFile); is taking a long time - about 3 seconds.

Is there a faster way of getting all the named ranges associated with excel sheet?

File excelFile = new File(filePath);
Workbook workbook = WorkbookFactory.create(excelFile);
int n = workbook.getNumberOfNames();

for (int i = 0; i < n; i++)
{
    Name nameObject = workbook.getNameAt(i);
    String formulaName = nameObject.getRefersToFormula();
    System.out.println("Named Range is :"+formulaName);
}

回答1:

I just submitted a patch to POI which fixes the horrible WorkbookFactory.create() execution time, you might want to look at it here:

https://issues.apache.org/bugzilla/show_bug.cgi?id=51585

Building POI is not really hard - just apply the patch to the vanilla 3.9 version.