Java

Load a Public Key from Base64 DER

Demonstrates the Chilkat PublicKey.LoadBase64 method, which loads a public key from standard Base64-encoded DER. The only argument is the Base64 string; whitespace within it is permitted.

Background: A public key in DER (binary) form is often carried as Base64 text so it can travel through channels that expect a string — a config value, a JSON field, a certificate export. This loader decodes that text and inspects the DER to determine the key type and structure automatically. It is the plain-Base64 counterpart to loading a full PEM block, which additionally has the BEGIN/END armor.

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Java

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[])
  {
    boolean success = false;

    //  Demonstrates the PublicKey.LoadBase64 method, which loads a public key from standard
    //  Base64-encoded DER.  The only argument is the Base64 string (whitespace is allowed).

    CkPublicKey pubKey = new CkPublicKey();

    //  The Base64 of the DER-encoded public key.
    String keyStr = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA...IDAQAB";

    success = pubKey.LoadBase64(keyStr);
    if (success == false) {
        System.out.println(pubKey.lastErrorText());
        return;
        }

    System.out.println("Loaded a " + pubKey.keyType() + " public key.");
  }
}