Eclipse Workspace In Use Or Cannot Be Created

You may recieve the error message “Eclipse Workspace In Use Or Cannot Be Created” From Eclipse when trying to start up Eclipse, this typically means that Eclipse is already running.  If you have not started Eclipse, try to locate Eclipse in your operating systems task manager and kill it. You can also consider killing any java processes running if you cant find any Eclipse processes.

A hint for the “Object foo is not a known entity type” errors from Glassfish

As a JavaEE-codemonkey you have perhaps noticed this error:

java.lang.IllegalArgumentException: Object: Ting@193c227 is not a known entity type.

This will occur when you have redeployed an app f.ex through Eclipse to Glassfish, the Glassfish server has not quite understood that it`s time to update its version, so what you need to do then is to simply restart the server (or domain).

One possible solution for Glassfish cluster node-agent startup problems

Just a quick hint for those of you who are experiencing problem with getting node-agents up and running in a Glassfish cluster.

If the problem is that the asadmin start-agent command simply times out/uses a long time to start, and even possibly returning a filenotfoundexception. The problem could be as simple as a firewall blocking traffic to/from the master-node. A quick way to check it is to simply disable the FW.

Note that if the master-node does not see the node-agent status, it is also caused by FW-issues, fix the FW and then restart the node-agent(s), then it all should work like a charm!