Excel转图片（Free Spire.XLS for Java）

import com.spire.xls.Workbook;
import com.spire.xls.Worksheet;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

public class Test {

    public static void main(String[] args) throws IOException {
        Workbook workbook = new Workbook();
        //加载Excel文档
        workbook.loadFromFile("test.xlsx");

        //获取第一张工作表
        Worksheet sheet = workbook.getWorksheets().get(0);

        //保存到图片
        BufferedImage bufferedImage = sheet.toImage(1, 1, sheet.getLastRow(), sheet.getLastColumn());

        //写出图片到文件
        ImageIO.write(bufferedImage, "PNG", new File("sheetToImage.png"));
    }

}