### Question:
ServiceBackupCallback extends IBackupCallback.Stub { @Override public void operationComplete(long result) throws RemoteException { mBackupManager.opComplete(mToken, result); } ServiceBackupCallback(IBackupManager backupManager, int token); @Override void operationComplete(long result);  }### Answer:
@Test public void testOperationComplete_callsBackupManagerOpComplete() throws Exception { IBackupManager backupManager = mock(IBackupManager.class); ServiceBackupCallback callback = new ServiceBackupCallback(backupManager, 0x68e); callback.operationComplete(7); verify(backupManager).opComplete(0x68e, 7); }