killbill-memoizeit

diff --git a/account/src/test/java/com/ning/billing/account/api/MockAccountUserApi.java b/account/src/test/java/com/ning/billing/account/api/MockAccountUserApi.java
new file mode 100644
index 0000000..56d781b
--- /dev/null
+++ b/account/src/test/java/com/ning/billing/account/api/MockAccountUserApi.java
@@ -0,0 +1,48 @@
+package com.ning.billing.account.api;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+public class MockAccountUserApi implements IAccountUserApi {
+    private final CopyOnWriteArrayList<IAccount> accounts = new CopyOnWriteArrayList<IAccount>();
+
+    @Override
+    public IAccount createAccount(IAccountData data) {
+        IAccount result = new Account().withKey(data.getKey())
+                                       .withName(data.getName())
+                                       .withEmail(data.getEmail())
+                                       .withPhone(data.getPhone())
+                                       .withBillCycleDay(data.getBillCycleDay())
+                                       .withCurrency(data.getCurrency());
+        accounts.add(result);
+        return result;
+    }
+
+    @Override
+    public IAccount getAccountByKey(String key) {
+        for (IAccount account : accounts) {
+            if (key.equals(account.getKey())) {
+                return account;
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public IAccount getAccountFromId(UUID uid) {
+        for (IAccount account : accounts) {
+            if (uid.equals(account.getId())) {
+                return account;
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public List<IAccount> getAccounts() {
+        return new ArrayList<IAccount>(accounts);
+    }
+
+}