Apache POI (Excel in Java) - Span Multiple Columns with Cell

apache_poi.java

import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;


HSSFWorkbook wb = new HSSFWorkbook();
        
Sheet sheet = wb.createSheet();


CellRangeAddress region = new CellRangeAddress( rowIdx, rowIdx, columnIdx, columnIdx+1);
sheet.addMergedRegion(region);