java - Java中如何获取证书信息

Question

我试图仅在 Java 中获取和读取证书。我应该查看哪些代码或示例才能获取网站的证书。

例如网站:

1. https://google.com
2. https://www.ssllabs.com/

我使用 URL 类吗？

URL url = new URL("https://google.com");

Answer 1

好吧，我刚刚知道如何获取我想要的信息。

public void certInformation(String aURL) throws Exception{
        URL destinationURL = new URL(aURL);
        HttpsURLConnection conn = (HttpsURLConnection) destinationURL.openConnection();
        conn.connect();
        Certificate[] certs = conn.getServerCertificates();
        for (Certificate cert : certs) {
            System.out.println("Certificate is: " + cert);
            if(cert instanceof X509Certificate) {
                    X509Certificate x = (X509Certificate ) cert;
                    System.out.println(x.getIssuerDN());
            }
        }
    }