(Java) Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    CkCert cert = new CkCert();

    // LoadFromFile will load virtually any certificate format file.
    // It will auto-recognize the format and load appropiately.
    boolean success = cert.LoadFromFile("/Users/chilkat/testData/cer/chilkat.cer");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    // Get the public key:
    CkPublicKey pubkey;

    pubkey = cert.ExportPublicKey();
    if (cert.get_LastMethodSuccess() == false) {
        System.out.println(cert.lastErrorText());
        return;
        }

    // Save to various formats:
    success = pubkey.SaveDerFile(false,"/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der");
    if (success != true) {
        System.out.println(pubkey.lastErrorText());

        return;
        }

    success = pubkey.SavePemFile(false,"/Users/chilkat/testData/pubkeys/chilkat.pem");
    if (success != true) {
        System.out.println(pubkey.lastErrorText());

        return;
        }

    success = pubkey.SaveDerFile(true,"/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der");
    if (success != true) {
        System.out.println(pubkey.lastErrorText());

        return;
        }

    success = pubkey.SaveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml");
    if (success != true) {
        System.out.println(pubkey.lastErrorText());

        return;
        }

    System.out.println("Public key exported to all file formats.");
  }
}