关于java：从证书中获取公钥

Obtaining public key from certificate

我正在尝试使用以下方法获取证书的公钥：

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FileInputStream fin = new FileInputStream("PathToCertificate");
CertificateFactory f = CertificateFactory.getInstance("X.509");
X509Certificate certificate = (X509Certificate)f.generateCertificate(fin);
PublicKey pk = certificate.getPublicKey();

但我收到以下错误：

1 2	Exception in thread"main" java.lang.ClassCastException: sun.security.x509.X509CertImpl cannot be cast to codec.x509.X509Certificate at sergas_testcertificates.Main.main(Main.java:54)

有人知道这个错误是怎么回事吗？

提前谢谢

相关讨论

1 2	X509Certificate certificate = (X509Certificate)f.generateCertificate(fin); PublicKey pk = certificate.getPublicKey();

因为您只提取公钥，所以可以使用证书类。工厂类将决定返回哪种类型的证书。

1 2	Certificate certificate = f.generateCertificate(fin); PublicKey pk = certificate.getPublicKey();

如果出于其他原因需要强制转换此证书，请检查导入并进行更改，x509证书应来自javax.security.cert。