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Java Requires Chilkat v11.0.0+

RSA Sign with PKCS8 Encrypted Key

See more RSA Examples

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature.

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

public class ChilkatExample {

    public static void main(String[] args) {
        // This example assumes the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        PrivateKey pkey = new PrivateKey();

        // Load the private key from an RSA PEM file:
        pkey.loadPkcs8EncryptedFile("privateKey.key", "myPassword");

        Rsa rsa = new Rsa();

        // Import the private key into the RSA object:
        try {
            rsa.usePrivateKey(pkey);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Return the signature in hex
        rsa.setEncodingMode("hex");

        String strData = "This is the string to be signed.";

        // Sign the string using the sha-1 hash algorithm.
        // Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
        String hexSig = rsa.signStringENC(strData, "sha-1");

        System.out.println(hexSig);
    }
}