How to read xlsx file from Java

Question

I'm building an app with Eclipse in Java. I want to read XLS file.

public Carico leggiOrdineDaFile_Mazzeo(Fornitore f,String file){
        try{
            FileInputStream inputStream = new FileInputStream(new File(file));
            Workbook workbook = new XSSFWorkbook(inputStream);
            Sheet firstSheet = workbook.getSheetAt(0);
            Iterator<Row> iterator = firstSheet.iterator();
            Carico ordine = new Carico();
            List<DettOrdini> listaArticoli = new ArrayList<DettOrdini>();

            while (iterator.hasNext()) {
                Row nextRow = iterator.next();
                Iterator<Cell> cellIterator = nextRow.cellIterator();

                while (cellIterator.hasNext()) {
                    Cell cell = cellIterator.next();

                    switch (cell.getCellType()) {
                    case Cell.CELL_TYPE_STRING:
                        System.out.print(cell.getStringCellValue());
                        break;
                    case Cell.CELL_TYPE_BOOLEAN:
                        System.out.print(cell.getBooleanCellValue());
                        break;
                    case Cell.CELL_TYPE_NUMERIC:
                        System.out.print(cell.getNumericCellValue());
                        break;
                    }
                    System.out.print(" - ");
                }
                System.out.println();
            }

            ((BufferedReader) workbook).close();
            inputStream.close();
}

But if I try to start my code, I have this error message:

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: org/apache/commons/collections4/ListValuedMap

I have imported in my project this library:

poi-3.17.jar
poi-excelant-3.17.jar
poi-ooxml-3.17.jar
poi-ooxml-schemas-3.17.jar
poi-scratchpad-3.17.jar
xmlbeans-2.6.0.jar
curveaspi-1.0.4.jar

Answer 1

As your error message suggests : you are simply missing an import org.apache.commons .

See for reference https://commons.apache.org/proper/commons-collections/