Application gets crashed while using KeyGuardManager below Android L

KeyGuardManager works fine above android L, but it throws exception in Android L and below.

I am using below function:

 @RequiresApi(api = Build.VERSION_CODES.M)
    private void createKey() {
        try {
            KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
            keyStore.load(null);
            KeyGenerator keyGenerator = KeyGenerator.getInstance(
                    KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore");
            keyGenerator.init(new KeyGenParameterSpec.Builder(KEY_NAME,
                    KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
                    .setBlockModes(KeyProperties.BLOCK_MODE_CBC)
                    .setUserAuthenticationRequired(true)
                    // Require that the user has unlocked in the last 30 seconds
                    .setUserAuthenticationValidityDurationSeconds(AUTHENTICATION_DURATION_SECONDS)
                    .setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_PKCS7)
                    .build());
            keyGenerator.generateKey();
        } catch (NoSuchAlgorithmException | NoSuchProviderException
                | InvalidAlgorithmParameterException | KeyStoreException
                | CertificateException | IOException e) {
            throw new RuntimeException("Failed to create a symmetric key", e);
        }
    }

But it throws below exception in Android L & below:

dalvikvm: Could not find class 'android.security.keystore.KeyGenParameterSpec$Builder', referenced from method com.example.myapp.MainActivity.createKey
java.lang.VerifyError: com/example/myapp/MainActivity
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1208)
at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2112)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)

I have also added condition that this function should be called above Android L only. Still I am getting above exception.

Any help would be appreciated.

The problem is in the encrypt method where you're trying to initialize the Cipher from KeyStore. Catch block is trying to catch UserNotAuthenticatedException which is implemented in Android 23+ so it gives you Class not found Exception. Rather than implementing catch block in this way, try this below code, it worked like a charm in my code.

private boolean tryEncrypt() {
        try {
            KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
            keyStore.load(null);
            SecretKey secretKey = (SecretKey) keyStore.getKey(KEY_NAME, null);
            Cipher cipher = Cipher.getInstance(
                    KeyProperties.KEY_ALGORITHM_AES + "/" + KeyProperties.BLOCK_MODE_CBC + "/"
                            + KeyProperties.ENCRYPTION_PADDING_PKCS7);
            cipher.init(Cipher.ENCRYPT_MODE, secretKey);
            cipher.doFinal(SECRET_BYTE_ARRAY);
            return true;
        } catch (Exception e) {
            if (e instanceof UserNotAuthenticatedException) {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                    showAuthenticationScreen();
                }
                return false;
            }
            if (e instanceof KeyPermanentlyInvalidatedException) {
                return false;
            }
            return false;
        }
    }