Problem11_Excel

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Map;
import java.util.TreeMap;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class Probl11_Excel_ {
    public static void main(String[] args) {
         Map<String,Double> officeAndIncome = new TreeMap<>();
         try(InputStream file = new FileInputStream(new File("Incomes-Report.xlsx"));
            XSSFWorkbook workbook = new XSSFWorkbook(file)) {
                XSSFSheet sheet = workbook.getSheetAt(0);
                java.util.Iterator<Row> rowIterator = sheet.iterator();
                while(rowIterator.hasNext()) {
                    Row row = rowIterator.next();
                    java.util.Iterator<Cell> cellIterator = row.cellIterator();
                    int cellNum = 0;
                    while(cellIterator.hasNext()) {
                        String office = "no office";
                        if (cellNum == 0) {
                            Cell cell = cellIterator.next();
                            office = cell.getStringCellValue();
                            boolean hasThisOffice = false;
                            for(String off:officeAndIncome.keySet()){
                                if ((off).equals(office)) {
                                    hasThisOffice = true;
                        }
                            }
                            if (!hasThisOffice) {
                                officeAndIncome.put(office,0.0);
                    }
                        }
                        if (cellNum == 5) {
                            Cell cell = cellIterator.next();
                            double income = cell.getNumericCellValue();
                            for(String off:officeAndIncome.keySet()){
                                if ((off).equals(office)) {
                            income+=officeAndIncome.get(off);
                        }
                            }
                            officeAndIncome.put(office,income);
                }
                    }
                }
                file.close();
                PrintWriter writer = new PrintWriter("output.txt", "UTF-8");
                for(String office : officeAndIncome.keySet()){
                    String line = office + " -> " + officeAndIncome.get(office) + "\n";
                    writer.println(line);
            }
                writer.close();

         } catch (FileNotFoundException e) {
                System.out.println("File Not Found.");
            } catch (IOException e) {
                e.printStackTrace();
            }
    }
}