This error still happens frequently.
I find that the fix:
if you experience problems again, try to do this
1. undeploy your app
2. stop glassfish
3. clean the directorys <glassfish-home>/glassfish/domains/domain1/generated/*/
4. start glassfish
5. deploy your app.
is not quite enough as I use virtual servers. After redeploying my app in step 5, I still need to make sure my app is deployed to the right Virtual servers and then restart again to get my virtual servers to pick up the app. It seems to deploy it to all virtual servers by default. Is there a way to tell netbeans which virtual server to deploy the app to and is the second restart really necessary? seems to me it shouldn't be.
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