When the server is in a project rather than in memory, persisting changes to the server (ie changing its username) will fail because the scheduling rule for starting the server does not include the ability to modify projects. This scenario will need to be identified (is server in memory or project) and a workspace job will need to be scheduled to properly persist the changes.
java.lang.IllegalArgumentException: Attempted to beginRule: L/Servers/Container Development Environment.server, does not match outer scope rule: Container Development Environment
at org.eclipse.core.runtime.Assert.isLegal(Assert.java:63)
at org.eclipse.core.internal.jobs.ThreadJob.illegalPush(ThreadJob.java:134)
at org.eclipse.core.internal.jobs.ThreadJob.push(ThreadJob.java:333)
at org.eclipse.core.internal.jobs.ImplicitJobs.begin(ImplicitJobs.java:85)
at org.eclipse.core.internal.jobs.JobManager.beginRule(JobManager.java:307)
at org.eclipse.core.internal.resources.WorkManager.checkIn(WorkManager.java:121)
at org.eclipse.core.internal.resources.Workspace.prepareOperation(Workspace.java:2188)
at org.eclipse.core.internal.resources.File.setContents(File.java:334)
at org.eclipse.core.internal.resources.File.setContents(File.java:434)
at org.eclipse.wst.server.core.internal.Base.saveToFile(Base.java:251)
at org.eclipse.wst.server.core.internal.Server.saveToFile(Server.java:471)
at org.eclipse.wst.server.core.internal.Base.doSave(Base.java:264)
at org.eclipse.wst.server.core.internal.Server.doSave(Server.java:466)
at org.eclipse.wst.server.core.internal.ServerWorkingCopy.save(ServerWorkingCopy.java:434)
at org.jboss.tools.openshift.cdk.server.core.internal.adapter.CDKServer.getPassword(CDKServer.java:124)
at org.jboss.tools.openshift.cdk.server.core.internal.adapter.controllers.CDKLaunchController.launch(CDKLaunchController.java:158)
at org.jboss.ide.eclipse.as.wtp.core.server.launch.ControllableServerLaunchConfiguration.launch(ControllableServerLaunchConfiguration.java:52)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:885)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:739)
at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:731)
at org.eclipse.wst.server.core.internal.Server.startImpl2(Server.java:3556)
at org.eclipse.wst.server.core.internal.Server.startImpl(Server.java:3492)
at org.eclipse.wst.server.core.internal.Server$StartJob.run(Server.java:367)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)