You can read/write Excel files with Apache POI or JExcelApi Java libraries.
Below are few examples.
Apache POI writing spreadsheet example:
import java.io.*;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFCell;
public class CreateExlFile{
public static void main(String[]args){
try{
String filename="C:/spreadsheet.xls" ;
HSSFWorkbook workbook=new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet("FirstSheet");
HSSFRow rowhead= sheet.createRow((short)0);
rowhead.createCell(0).setCellValue("No.");
rowhead.createCell(1).setCellValue("First Name");
rowhead.createCell(2).setCellValue("Last Name");
HSSFRow row= sheet.createRow((short)1);
row.createCell(0).setCellValue("1");
row.createCell(1).setCellValue("Edith");
row.createCell(2).setCellValue("Coleman");
FileOutputStream fileOut = new FileOutputStream(filename);
workbook.write(fileOut);
fileOut.close();
System.out.println("The file was successfully generated!");
} catch ( Exception ex ) {
System.out.println(ex);
}
}
}
JExcelApi writing spreadsheet example:
import java.io.File;
import java.util.Date;
import jxl.*;
import jxl.write.*;
WritableWorkbook workbook = Workbook.createWorkbook(new File("output.xls"));
WritableSheet sheet = workbook.createSheet("FirstSheet", 0);
//The following code fragment puts a label in cell A3, and the number 3.14159 in cell D5.
Label label = new Label(0, 2, "A label record");
sheet.addCell(label);
Number number = new Number(3, 4, 3.1459);
sheet.addCell(number);
workbook.write();
workbook.close();