Java 生成透明图片

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
import javax.swing.\*;
import java.awt.\*;
import java.awt.font.FontRenderContext;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
/\*\*
 \* 图片处理工具类
 \* @author maruifu
public class ImageUtils1 {
    private static int[] getWidthAndHeight(String text, Font font) {
        Rectangle2D r = font.getStringBounds(text, new FontRenderContext(
                AffineTransform.getScaleInstance(1, 1), false, false));
        int unitHeight = (int) Math.floor(r.getHeight());
        // 获取整个str用了font样式的宽度这里用四舍五入后+1保证宽度绝对能容纳这个字符串作为图片的宽度
        int width = (int) Math.round(r.getWidth()) + 1;
        // 把单个字符的高度+3保证高度绝对能容纳字符串作为图片的高度
        int height = unitHeight + 3;
        return new int[]{width, height};
    public static void createImage(String text, String filePath,String fontName,int fontSize)  {
        ImageOutputStream imageOutputStream = null;
        try {
            Font font = new Font(fontName, Font.BOLD,fontSize);
            // 获取font的样式应用在输出内容上整个的宽高
            int[] arr = getWidthAndHeight(text, font);
            // 设置背景宽高
            int width = arr[0];
            int height = arr[1];
            BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE\_4BYTE\_ABGR);
            // 获取图形上下文对象
            Graphics2D graphics = (Graphics2D)image.getGraphics();
            graphics.clearRect(0, 0, width, height);
            // 填充
            graphics.fillRect(0, 0, width, height);
            // 设定字体大小及样式
            graphics.setFont(font);
            // 字体颜色
            graphics.setColor(Color.BLACK);
            // 描绘字符串
            graphics.drawString(text, 0,   font.getSize());
            // 图片透明度
            setTransparency(image, graphics);
            File jpgFile = new File(filePath);
            if(!jpgFile.exists()) {
                jpgFile.createNewFile();
            // 创建图片输出流对象，基于文件对象
            imageOutputStream = ImageIO.createImageOutputStream(jpgFile);
            // 写入
            ImageIO.write(image, FilenameUtils.getExtension(filePath),imageOutputStream);
        } catch (IOException e) {
            log.error("生成图片失败{}",e);
        } finally {
            // 关闭流
            IOUtils.closeQuietly(imageOutputStream);
    private static void setTransparency(BufferedImage image, Graphics2D graphics) {
        int alpha = 0;
        // 外层遍历是Y轴的像素
        for (int y = image.getMinY(); y < image.getHeight(); y++) {
            // 内层遍历是X轴的像素
            for (int x = image.getMinX(); x < image.getWidth(); x++) {
                int rgb = image.getRGB(x, y);
                // 对当前颜色判断是否在指定区间内
                if (colorInRange(rgb)) {
                    alpha = 0;
                } else {
                    // 设置为不透明
                    alpha = 255;
                // #AARRGGBB 最前两位为透明度
                rgb = (alpha << 24) | (rgb & 0x00ffffff);
                image.setRGB(x, y, rgb);
        // 绘制设置了RGB的新图片
        graphics.drawImage(image, 0, 0, null);
        //释放画笔
        graphics.dispose();
            ImageIcon imageIcon = new ImageIcon(image);
            BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE\_4BYTE\_ABGR);
            // 获取画笔
            Graphics2D g2D = (Graphics2D) bufferedImage.getGraphics();
            // 绘制Image的图片
            g2D.drawImage(imageIcon.getImage(), 0, 0, null);
            // 图片透明
            setTransparency(bufferedImage, g2D);
            // 生成图片为PNG
            ImageIO.write(bufferedImage, FilenameUtils.getExtension(sourcePath), new File(targetPath));
        } catch (IOException e) {
            log.error("设置图片透明失败{}",e);
        // 通过RGB三分量来判断当前颜色是否在指定的颜色区间内
        if (red >= colorRange && green >= colorRange && blue >= colorRange) {
            return true;