PrivatePublicKeys.java

// Convertendo os bytes salvos em instâncias
byte[] privateKeyBytes = privateKey.getEncoded();
byte[] publicKeyBytes = publicKey.getEncoded();

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

EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);

EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyBytes);
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);