code: public boolean verify(byte[] data, byte[] sign) {
  		lock.lock();
  		try {
  			signature.initVerify(this.publicKey);
  			signature.update(data);
  			return signature.verify(sign);
  		} catch (Exception e) {
  			throw new CryptoException(e);
  		} finally {
  			lock.unlock();
  		}
  	}
docs: 用公钥检验数字签名的合法性
  
  @param data 数据
  @param sign 签名
  @return 是否验证通过