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package com.bank.agreement.service.citic.settleAccount;

import sun.misc.BASE64Encoder; import java.io.FileInputStream; import java.security.PublicKey; import java.security.cert.CertificateFactory; import java.security.cert.X509Certificate;

/**

• @author zhujiangtao
• @date 2019/11/29 10:02 */

public class Cerdemo { /** * 该示例展示了如何从文件中读取X.509证书，提取公钥并进行BASE64编码。 */ public static void main(String[] args) throws Exception { CertificateFactory cf = CertificateFactory.getInstance("X.509"); X509Certificate cert = (X509Certificate) cf.generateCertificate(new FileInputStream("e:/citic.cer")); PublicKey publicKey = cert.getPublicKey(); BASE64Encoder base64Encoder=new BASE64Encoder(); String publicKeyString = base64Encoder.encode(publicKey.getEncoded()); System.out.println("-----------------公钥 --------------------"); System.out.println(publicKeyString); System.out.println("-----------------公钥 --------------------"); } }