code: public static String getAlgorithmAfterWith(String algorithm) {
  		Assert.notNull(algorithm, "algorithm must be not null !");
  		int indexOfWith = StrUtil.lastIndexOfIgnoreCase(algorithm, "with");
  		if (indexOfWith > 0) {
  			algorithm = StrUtil.subSuf(algorithm, indexOfWith + "with".length());
  		}
  		if ("ECDSA".equalsIgnoreCase(algorithm) || "SM2".equalsIgnoreCase(algorithm)) {
  			algorithm = "EC";
  		}
  		return algorithm;
  	}
docs: 获取用于密钥生成的算法<br>
  获取XXXwithXXX算法的后半部分算法，如果为ECDSA或SM2，返回算法为EC
  
  @param algorithm XXXwithXXX算法
  @return 算法