读取Cert格式证书的密钥

不想存储Cert证书内容，只想存储证书密钥，可通过以下实现读取证书的密钥出来： 

 1 package com.zat.ucop.service.util;
 2 
 3 import sun.misc.BASE64Encoder;
 4 
 5 import java.io.FileInputStream;
 6 import java.security.PublicKey;
 7 import java.security.cert.CertificateFactory;
 8 import java.security.cert.X509Certificate;
 9 
10 /**
11  * 读取cert格式证书的密钥.
12  *
13  * @author weixiong.cao
14  * @date 2019/4/3
15  */
16 public class ReadCerDemo {
17     public static void main(String[] args) throws Exception {
18         String keyStorePath = "E:/mpay公钥/client_02.cer";
19 
20         CertificateFactory cf = CertificateFactory.getInstance("X.509");
21         X509Certificate cert = (X509Certificate) cf.generateCertificate(new FileInputStream(keyStorePath));
22         PublicKey publicKey = cert.getPublicKey();
23         BASE64Encoder base64Encoder = new BASE64Encoder();
24         String publicKeyString = base64Encoder.encode(publicKey.getEncoded());
25         System.out.println("-----------------公钥--------------------");
26         System.out.println(publicKeyString);
27         System.out.println("-----------------公钥--------------------");
28     }
29 }