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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.

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Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.PrivateKey;

public class ChilkatExample {

    public static void main(String[] args) {
        // Load a private key to export.
        PrivateKey privKey = new PrivateKey();
        try {
            privKey.loadPemFile("qa_data/private.pem");

            // Save using the traditional/preferred unencrypted DER representation.
            privKey.savePkcs1File("qa_output/private_pkcs1.der");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

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