类加载器获取文件并转换成流

public class ByteUtils {
    private static byte[] dataPre = null;
    static {
        try {
            dataPre = getDataFile(new File(ByteUtils.class.getResource("icon-img.jpg").toURI()));
        } catch (URISyntaxException e) {
            e.printStackTrace();
        }
    }
    public static ByteArrayOutputStream getDate(byte[] data) {
        ByteArrayOutputStream baos = null;
        if (data == null) {
            data = dataPre;
        }
        try {
            baos = new ByteArrayOutputStream();
            baos.write(Base64.encodeBase64(data));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return baos;
    }

    public static byte[] getDataFile(File file) {
        if (null != file) {
            byte[] bFile = new byte[(int) file.length()];
            try {
                FileInputStream fileInputStream = new FileInputStream(file);
                fileInputStream.read(bFile);
                fileInputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
            return bFile;
        }
        return null;
    }
}