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Java

Save a Private Key as a Traditional DER File

See more Private Key Examples

Demonstrates the Chilkat PrivateKey.SavePkcs1File method, which saves the key using the traditional/preferred unencrypted DER representation. The only argument is the destination path.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This writes the older, algorithm-specific DER structure — useful for compatibility with tools that predate or do not accept PKCS #8. For new work, PKCS #8 (SavePkcs8File) is more interoperable. The output is unencrypted, so protect the file accordingly.

Chilkat Java Downloads

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;

    //  Load a private key to export.
    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadPemFile("qa_data/private.pem");
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    //  Save using the traditional/preferred unencrypted DER representation.
    success = privKey.SavePkcs1File("qa_output/private_pkcs1.der");
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    System.out.println("Saved.");
  }
}