killbill-memoizeit

diff --git a/payment/src/main/java/org/killbill/billing/payment/api/DefaultPaymentApi.java b/payment/src/main/java/org/killbill/billing/payment/api/DefaultPaymentApi.java
index 2674a79..41be1e4 100644
--- a/payment/src/main/java/org/killbill/billing/payment/api/DefaultPaymentApi.java
+++ b/payment/src/main/java/org/killbill/billing/payment/api/DefaultPaymentApi.java
@@ -116,7 +116,7 @@ public class DefaultPaymentApi extends DefaultApiBase implements PaymentApi {
     }
 
     @Override
-    public Payment createAuthorizationWithPaymentControl(final Account account, final UUID paymentMethodId, @Nullable final UUID paymentId, final BigDecimal amount, final Currency currency,
+    public Payment createAuthorizationWithPaymentControl(final Account account, @Nullable final UUID paymentMethodId, @Nullable final UUID paymentId, final BigDecimal amount, final Currency currency,
                                                          @Nullable final String paymentExternalKey, @Nullable final String paymentTransactionExternalKey,
                                                          final Iterable<PluginProperty> properties, final PaymentOptions paymentOptions, final CallContext callContext) throws PaymentApiException {
         final List<String> paymentControlPluginNames = toPaymentControlPluginNames(paymentOptions, callContext);
@@ -602,7 +602,7 @@ public class DefaultPaymentApi extends DefaultApiBase implements PaymentApi {
     }
 
     @Override
-    public Payment createCreditWithPaymentControl(final Account account, final UUID paymentMethodId, @Nullable final UUID paymentId, final BigDecimal amount, final Currency currency,
+    public Payment createCreditWithPaymentControl(final Account account, @Nullable final UUID paymentMethodId, @Nullable final UUID paymentId, final BigDecimal amount, final Currency currency,
                                                   @Nullable final String paymentExternalKey, @Nullable final String paymentTransactionExternalKey,
                                                   final Iterable<PluginProperty> properties, final PaymentOptions paymentOptions, final CallContext callContext) throws PaymentApiException {
         final List<String> paymentControlPluginNames = toPaymentControlPluginNames(paymentOptions, callContext);
@@ -627,14 +627,11 @@ public class DefaultPaymentApi extends DefaultApiBase implements PaymentApi {
 
             final InternalCallContext internalCallContext = internalCallContextFactory.createInternalCallContext(account.getId(), callContext);
 
-            // TODO validate if the code is located properly here
-            // The code should understand that the external payment method needs to be created
-            // if it doesn't exist yet and trigger a CREDIT using the (built-in) external payment plugin.
-            final UUID nonNullPaymentMethodId = (paymentMethodId != null) ?
-                                               paymentMethodId :
-                                               paymentMethodProcessor.createOrGetExternalPaymentMethod(UUIDs.randomUUID().toString(), account, properties, callContext, internalCallContext);
+            final UUID resolvedPaymentMethodId = (paymentMethodId == null && paymentOptions.isExternalPayment()) ?
+                                                                                              paymentMethodProcessor.createOrGetExternalPaymentMethod(UUIDs.randomUUID().toString(), account, properties, callContext, internalCallContext) :
+                                                                                              paymentMethodId;
 
-            payment = pluginControlPaymentProcessor.createCredit(IS_API_PAYMENT, account, nonNullPaymentMethodId, paymentId, amount, currency, paymentExternalKey, paymentTransactionExternalKey,
+            payment = pluginControlPaymentProcessor.createCredit(IS_API_PAYMENT, account, resolvedPaymentMethodId, paymentId, amount, currency, paymentExternalKey, paymentTransactionExternalKey,
                                                                                properties, paymentControlPluginNames, callContext, internalCallContext);
 
             paymentTransaction = findPaymentTransaction(payment, paymentTransactionExternalKey);

diff --git a/payment/src/main/java/org/killbill/billing/payment/core/PaymentMethodProcessor.java b/payment/src/main/java/org/killbill/billing/payment/core/PaymentMethodProcessor.java
index a0203d1..e9d6761 100644
--- a/payment/src/main/java/org/killbill/billing/payment/core/PaymentMethodProcessor.java
+++ b/payment/src/main/java/org/killbill/billing/payment/core/PaymentMethodProcessor.java
@@ -228,7 +228,7 @@ public class PaymentMethodProcessor extends ProcessorBase {
                 final PaymentPluginApi pluginApi = getPaymentPluginApi(paymentMethodModelDao.getPluginName());
                 paymentMethodPlugin = pluginApi.getPaymentMethodDetail(paymentMethodModelDao.getAccountId(), paymentMethodModelDao.getId(), properties, tenantContext);
             } catch (final PaymentPluginApiException e) {
-                throw new PaymentApiException(ErrorCode.PAYMENT_GET_PAYMENT_METHODS, paymentMethodModelDao.getAccountId(), paymentMethodModelDao.getId());
+                throw new PaymentApiException(e, ErrorCode.PAYMENT_GET_PAYMENT_METHODS, paymentMethodModelDao.getAccountId(), paymentMethodModelDao.getId());
             }
         } else {
             paymentMethodPlugin = null;