aswi2020vldc-gitlab/src/main/java/vldc/aswi/utils/ExporterXLSX.java @ d12e5d6c

package vldc.aswi.utils;

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

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

/**
 * Class used for exporting data to XLSX
 */
public class ExporterXLSX {

    /**
     * !!!DUMMY!!!
     * Exports data to .xlsx file
     * @param tableName name of the table
     */
    public static void export(String tableName) {

        //temporary dummy implementation, used for testing
        String[] columns = new String[] {"studuje", "nestuduje"};
        String[] rows = new String[] {"fav", "fst"};
        String[] data = new String[] {"1", "2", "3", "4"};

        Workbook workbook = new XSSFWorkbook();

        Sheet sheet = workbook.createSheet(tableName);

        Font colRowNameFont = workbook.createFont();
        colRowNameFont.setBold(true);
        colRowNameFont.setFontHeightInPoints((short) 16);
        colRowNameFont.setColor(IndexedColors.BLACK.getIndex());

        Font dataFont = workbook.createFont();
        dataFont.setBold(false);
        dataFont.setFontHeightInPoints((short) 12);
        dataFont.setColor(IndexedColors.BLACK.getIndex());

        CellStyle colRowStyle = workbook.createCellStyle();
        colRowStyle.setFont(colRowNameFont);

        CellStyle dataStyle = workbook.createCellStyle();
        dataStyle.setFont(dataFont);

        Row descRow = sheet.createRow(0);

        for (int i = 0; i < 2; i++) {
            Cell cell = descRow.createCell(i + 1);
            cell.setCellValue(columns[i]);
            cell.setCellStyle(colRowStyle);
        }

        for (int i = 0; i < 2; i++) {
            Row row = sheet.createRow(i + 1);
            Cell nameCell = row.createCell(0);
            nameCell.setCellValue(rows[i]);
            nameCell.setCellStyle(colRowStyle);

            Cell cell1 = row.createCell(1);
            cell1.setCellValue(data[i + i + 1]);
            cell1.setCellStyle(dataStyle);

            Cell cell2 = row.createCell(2);
            cell2.setCellValue(data[i + i + 1]);
            cell2.setCellStyle(dataStyle);
        }

        for (int i = 0; i < 3; i++) {
            sheet.autoSizeColumn(i);
        }

        //merge of columns, will be used for column headers
        //sheet.addMergedRegion(new CellRangeAddress(0,0,1,2));

        FileOutputStream streamOut = null;

        try {
            streamOut = new FileOutputStream("out.xlsx");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        try {
            workbook.write(streamOut);
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            if (streamOut != null) {
                streamOut.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            workbook.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}