src/org/nutz/img/Images.java
public static String encodeBase64(File targetFile) {
        BufferedImage image = null;

        try {
            image = ImageIO.read(targetFile);
        }
        catch (IOException e) {
            throw Lang.wrapThrow(e);
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        BufferedOutputStream bos = new BufferedOutputStream(baos);
        image.flush();
        try {
            ImageIO.write(image, Files.getSuffixName(targetFile), bos);
            bos.flush();
            bos.close();
        }
        catch (IOException e) {
            throw Lang.wrapThrow(e);
        }

        byte[] bImage = baos.toByteArray();

        return Base64.encodeToString(bImage, false);
    }
public static String encodeBase64(File targetFile) {
        BufferedImage image = null;

        try {
            image = ImageIO.read(targetFile);
        }
        catch (IOException e) {
            throw Lang.wrapThrow(e);
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        BufferedOutputStream bos = new BufferedOutputStream(baos);
        image.flush();
        try {
            ImageIO.write(image, Files.getSuffixName(targetFile), bos);
            bos.flush();
            bos.close();
        }
        catch (IOException e) {
            throw Lang.wrapThrow(e);
        }

        byte[] bImage = baos.toByteArray();

        return Base64.encodeToString(bImage, false);
    }
生成该图片对应的 Base64 编码的字符串

@param targetFile
图片文件
@return 图片对应的 Base64 编码的字符串