I'm struggling with a bug that is closely related to this thread. I think
transactions all by themselves will not work here. This is because the
transactions are optimistic. So, if the transaction looks like this (pseudo
code)
pm.currentTransaction.begin();
Object preexistingEntity =
OK, here is something that looks promising;
http://squeeville.com/2009/01/30/add-a-unique-constraint-to-google-app-engine/
This shows a solution in python, but the concept is applicable to Java.
Basically, for the unique field, you create another database entity and
derive a primary Key
Yes, I do this with JDO. Just add to you queue within the current
transaction, for instance;
PersistenceManager pm = PMF.get().getPersistenceManager();
try
{
//
// start transaction so we can atomically check the secondary key
//
pm.currentTransaction().begin();
If you right-click your appengine project and choose properties from
the contextual menu (or just select the project and select properties
item in the Project menu on the menubar), you get the project
properties. Select the Google in the navbar on the left, then select
App Engine from the tree
I use Windows and I have the same problem when I upgrade and sometimes
when I create a new workspace. (tried to use Ubuntu, but can't get my
Adobe Flex plugin and Google plugin to both play nice). It seems the
the plugin update changes the SDK version, but does not copy the new
jars; it leaves the
Thanks for starting this thread. I have my Junit tests working,
including my datastore tests, but I have a question regarding project
setup. I suppose this is more of an Eclipse question than anything
else, but perhaps you can help. I've worked in NetBeans prior, and I
can setup a 'test' folder
There are some proposed new features for GAE to allow apps to keep
their byte-code 'warm', either on the application server, or as a pre-
initialized image on disk that can be loaded and not incur a full
initialization. Check out this issue, contribute suggestions and
vote for it if you want to
