java base64字符串图片转字节流及文件扩展名

java base64 img str to byte stream

public static Map base64StrToByte(String base64Imgstr) {

        String imageBase64Str="" ,extName="";
        Map m = new HashMap<String,Object>();
        StringBuffer fileName = new StringBuffer();
        if (base64Imgstr.indexOf("data:image/png;") != -1) {
            imageBase64Str = base64Imgstr.replace("data:image/png;base64,", "");
            extName = ".png";
        } else if (base64Imgstr.indexOf("data:image/jpeg;") != -1) {
            imageBase64Str = base64Imgstr.replace("data:image/jpeg;base64,", "");
            extName = ".jpeg";
        }
        try {
            BASE64Decoder decoder =new BASE64Decoder();
            byte[] imageByte=decoder.decodeBuffer(imageBase64Str);
            m.put("extName",extName);
            m.put("byte",imageByte);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return m;

    }

extName 扩展名
byte 图片文件流，可保存到本地