Unit Testing XG Cross Group Transaction in App Engine Java JDO

Question

I have a cross group transaction in app engine java jdo. It works great on the local dev app engine server. However, from unit testing, I get a `java.lang.IllegalArgumentException: transactions on multiple entity groups only allowed in High Replication applications`. Is it possible to simulate a High Replication Application using LocalServiceTestHelper? I am using 1.6.6. Here is my class, you can run it as it is to reproduce: ``` public class Ds2Test { private final LocalServiceTestHelper helper = new LocalServiceTestHelper(new LocalDatastoreServiceTestConfig()); private static final PersistenceManagerFactory pmfXgInstance = JDOHelper.getPersistenceManagerFactory("xg-transactions"); @Before public void setUp() { helper.setUp(); } @After public void tearDown() { helper.tearDown(); } @Test public void testXgTransaction() throws Exception { PersistenceManager xgPm = pmfXgInstance.getPersistenceManager(); Transaction xgTx = xgPm.currentTransaction(); xgTx.begin(); xgTx.commit(); xgPm.clos…

Accepted Answer

Ok. I found what needs to be done.

```
private final LocalServiceTestHelper helper =
            new LocalServiceTestHelper(new LocalDatastoreServiceTestConfig()**.setDefaultHighRepJobPolicyUnappliedJobPercentage(100))**;
```

As seen on: https://developers.google.com/appengine/docs/java/tools/localunittesting#Writing_HRD_Datastore_Tests

A little obscure setting, but there it is.

Unit Testing XG Cross Group Transaction in App Engine Java JDO

Solution

Problem