java excel

package com.example.demo;

import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.SharedStringsTable;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.springframework.stereotype.Component;
import org.xml.sax.XMLReader;

import javax.print.attribute.standard.DateTimeAtCompleted;
import java.io.*;
import java.util.HashMap;
import java.util.Iterator;

@Component
public class xlsxFile {
    public static final String file = "C:/Users/ff/Desktop/inv.xlsx"    ;

    public static void main(String[] arags) throws IOException, OpenXML4JException, FileNotFoundException {
        Workbook wb = WorkbookFactory.create(new File(file));
        DataFormatter dataFormatter = new DataFormatter();
        wb.forEach(sheet -> {
            if(sheet.getSheetName().contains("VM")) {
                try {
                    content(sheet,dataFormatter);
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                }
            }
            });
    }

    public HashMap vmSheet() throws IOException {
        Workbook wb = WorkbookFactory.create(new File(file));
        DataFormatter dataFormatter = new DataFormatter();
        Sheet sheet = wb.getSheetAt(1);
        return showContent(sheet,dataFormatter);
    }

    public HashMap showContent(Sheet sheet, DataFormatter df) throws FileNotFoundException {
        HashMap hm = new HashMap<String, String>();
        int lastRow = sheet.getLastRowNum();
        Iterator<Row> rowIterator = sheet.iterator();
        while (rowIterator.hasNext()) {
            Row row = rowIterator.next();
            String key = null;
            String value = null;
            Iterator<Cell> cell = row.cellIterator();
            while (cell.hasNext()) {
                Cell c = cell.next();
                int columnIndex = c.getColumnIndex();
                if (columnIndex == 0) {
                    key = c.getStringCellValue();
                }
                if (columnIndex == 2) {
                    value = c.getStringCellValue();
                }
                if (key != null & value != null) {
                    hm.put(key, value);
                }
            }
        }
        return hm;
    }

    public static void content(Sheet sheet,DataFormatter dt) throws FileNotFoundException {
        host h = new host();
        System.setOut(new PrintStream(new FileOutputStream("C:/Users/ff/Desktop/inv.txt")));
        sheet.forEach(row -> {
            row.forEach(
                    cell -> {
                        String cellValue = dt.formatCellValue(cell);
                        if ((cell.getColumnIndex() ==  0 || cell.getColumnIndex() ==  2 )  && cell.getRowIndex() > 0 && cellValue.length() !=0 ) {
                            System.out.printf("%-20s",cellValue);
                        }
                    });
            System.out.println();
        });
    }
}