Java Utililty Methods Key Pair Create

return new SecretKeySpec(KEY_VALUE_128_BIT, AES_ALGO);

try {
    MessageDigest digester = MessageDigest.getInstance("MD5");
    int length = (keyLength + 15) / 16 * 16;
    byte[] passwordBytes = password.getBytes("UTF-8");
    byte[] temp = digester.digest(passwordBytes);
    byte[] key = Arrays.copyOf(temp, length);
    for (int i = 1; i < length / 16; i++) {
        temp = Arrays.copyOf(temp, 16 + passwordBytes.length);
...

final byte[] keyVal = Base64.getDecoder().decode(secKey.getBytes());
final Key key = new SecretKeySpec(keyVal, algorithm);
return key;

return generateKeyPair(1024);

try {
    final KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
    keyPairGenerator.initialize(KEY_SIZE);
    return keyPairGenerator.generateKeyPair();
} catch (NoSuchAlgorithmException e) {
    throw new RuntimeException(e);

KeyPairGenerator keyGen = KeyPairGenerator.getInstance(ALGORITHM);
keyGen.initialize(keyLength);
KeyPair keyPair = keyGen.generateKeyPair();
return keyPair;

return generateKeyPair("RSA");

if (generator == null) {
    generator = KeyPairGenerator.getInstance("RSA");
generator.initialize(2048);
return generator.genKeyPair();

KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
keyPairGenerator.initialize(getKeySize());
KeyPair keyPair = keyPairGenerator.generateKeyPair();
return keyPair;

KeyPairGenerator gen = KeyPairGenerator.getInstance(encryptionAlgorithm);
gen.initialize(keysize);
return gen.generateKeyPair();