RSA加签报错，请大神解决

1、公钥和私钥这边已经匹配过了是正常的

2、使用RSA加密方法加密

String sign = new String(Base64.encodeBase64(RSAUtil.sign(inputContent, privateKeyCode)),"utf-8");

直接报错java.security.SignatureException: Could not sign data  inputContent是需要加密的字符串转字节；privateKeyCode是RSA私钥转字节

导的包不对吧

import lombok.SneakyThrows;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import java.util.Base64;

/**
 * @author liuyh
 * @Description:
 * @date 2020/10/269:53
 */
public class BaseUtils {
    final static BASE64Encoder encoder = new BASE64Encoder();
    final static BASE64Decoder decoder = new BASE64Decoder();

    //加密
    @SneakyThrows
    public static String getEncoder(String msg) {
        byte[] textByte = msg.getBytes("UTF-8");
        String encodedText = encoder.encode(textByte);
        return encodedText;
    }

    //解密
    public static String getDecoder(String msg) throws Exception {
        return (new String(decoder.decodeBuffer(msg), "UTF-8"));
    }
}