poi-3.5-beta1 "new XSSFWorkbook();" Throws "org/openxml4j/exceptions/InvalidFormatException"

[Dobson, Paul L CTR USAF AFMC 416 SCMS/OBN]

I'm trying to get a head start migrating some POI code to use OOXML
using poi-3.5-beta1.

 

The following lines throws a
"org/openxml4j/exceptions/InvalidFormatException"

 

import org.apache.poi.xssf.usermodel.XSSFWorkbook;

XSSFWorkbook wb = null;

wb = new XSSFWorkbook(); //Exception thrown in this line.

 

Thanks in advance for any input/suggestions.

 

Paul Dobson