Java,Android - Get RSAPrivateKey and RSAPublicKey from String

test.java

import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;


try {
    String privateKeyContent = sharedPreferences.getString("SAMPLE_KEY_PRI",null); // load private key here
    String publicKeyContent = sharedPreferences.getString("SAMPLE_KEY_PUB",null); //load public key here

    privateKeyContent = privateKeyContent.replaceAll("\\n", "")
            .replace("-----BEGIN PRIVATE KEY-----", "")
            .replace("-----END PRIVATE KEY-----", "")
            .replaceAll("\\s+","");
    publicKeyContent = publicKeyContent.replaceAll("\\n", "")
            .replace("-----BEGIN PRIVATE KEY-----", "")
            .replace("-----END PRIVATE KEY-----", "")
            .replaceAll("\\s+","");

    KeyFactory kf = KeyFactory.getInstance("RSA");

    PKCS8EncodedKeySpec keySpecPKCS8 = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKeyContent));
    RSAPrivateKey privKey = (RSAPrivateKey) kf.generatePrivate(keySpecPKCS8);

    X509EncodedKeySpec keySpecX509 = new X509EncodedKeySpec(Base64.getDecoder().decode(publicKeyContent));
    RSAPublicKey pubKey = (RSAPublicKey) kf.generatePublic(keySpecX509); 
}catch (Exception e){
    e.printStackTrace();
}



// Used with lib ==> implementation 'com.blakequ.rsa:rsa:1.1'
//