forCurrentThread() not working in unit test

[merrickluo]

In our application, we use thread to write and read database, so we wrapped all query method with forCurrentThread, it works great, but when I writing a unit test with Robolectric, greendao complain about query not on the owner thread. If I directly write and read data in test, it's working too. Hope someone could help me find out what happened here.

[greenrobot]

Is there a stack trace you can post? Please investigate and provide more data. How can you be certain it's a greenDAO issue?

[merrickluo]

Sorry for that, I just create a new project to test this problem, it seems to be a Robolectric problem, the android.os.Process.myTid() always return 0, so when I call forCurrentThread(), the query's ownerThread is not being changed.

[merrickluo]

Q forCurrentThread() {
    int threadId = Process.myTid(); // always 0 in Robolectric
    synchronized (queriesForThreads) {
        WeakReference<Q> queryRef = queriesForThreads.get(threadId);
        Q query = queryRef != null ? queryRef.get() : null;
        if (query == null) {
            gc();
            query = createQuery();
            queriesForThreads.put(threadId, new WeakReference<Q>(query));
        } else {
            System.arraycopy(initialValues, 0, query.parameters, 0, initialValues.length);
        }
        return query;
    }
}

here is the source I find this problem, I wonder why not just use Thread.currentThead().getId() for the key?

[dcowley]

This issue is also related to running Android applications on a BB10 device. When the app is killed but continues to create and execute queries in the background, a DaoException is thrown because Thread.currentThread() != ownerThread.

From my understanding, Process.myTid() is OS-dependant, whereas Thread.currentThread().getId() (Java) is platform independent.

Using Thread.currentThread().getId() solves the issue of the application crashing on BB, and works for both BB and Android devices.

Thread.currentThread().getId() returns a long, so it may be worthwhile using LongSparseArray rather than casting the returned long to an int.

[greenrobot]

Does this still apply to Robolectric 3?

[merrickluo]

@greenrobot yes, still 0 for Process.myTid().

[greenrobot]

Fixed in 013af9c