Solving 409 conflict error in Eclipse

Today more than couple of hours I was breaking my head for this 409 conflict error eclipse, while working with google-app-engine. The error appeared as:

Unable to update app: Error posting to URL : http://appengine.google.com/api/appversion/create?app_id=mybdaywisherversion=1
409 conflict
Another transaction for this user is already in progress for this app and major version. That user can undo the transaction with appcfg.py’s “rollback” command.

After a long browsing and experiment, I got the solution to be like this:

Open Command Prompt and change the location to your application directory.

Then run appcfg file that is resides in the eclipse plugin directory with rollback command. I have installed my eclipse in C: only, so my command goes like this:

“C:\eclipse\plugins\com.google.appengine.eclipse.sdkbundle.1.3.7_1.3.7.v201008311427\appengine-java-sdk-1.3.7\bin\appcfg” rollback war

After this, everything worked fine.

Open existing project in eclipse

As I am a Netbeans user, while working with eclipse, I am finding some options in a new way. Just before I found difficult to open the existing project that has been closed. Like other IDE, here we don’t get Open Project option. Here we need to import the project from,

File > Import > General > Existing Project into Workspace