java.lang.NullPointerException
        at org.netbeans.core.startup.layers.ArchiveURLMapper.getURL(ArchiveURLMapper.java:82)
        at org.openide.filesystems.URLMapper.findURL(URLMapper.java:136)
        at org.netbeans.modules.j2ee.deployment.impl.DeployOnSaveManager.startListening(DeployOnSaveManager.java:169)
        at org.netbeans.modules.j2ee.deployment.devmodules.api.Deployment.enableCompileOnSaveSupport(Deployment.java:279)
        at org.netbeans.modules.maven.j2ee.POHImpl.refreshAppServerAssignment(POHImpl.java:208)
        at org.netbeans.modules.maven.j2ee.POHImpl.projectOpened(POHImpl.java:115)
        at org.netbeans.spi.project.ui.ProjectOpenedHook$1.projectOpened(ProjectOpenedHook.java:81)
        at org.netbeans.modules.project.ui.OpenProjectList.notifyOpened(OpenProjectList.java:1059)
        at org.netbeans.modules.project.ui.OpenProjectList.doOpenProject(OpenProjectList.java:1110)
        at org.netbeans.modules.project.ui.OpenProjectList.doOpen(OpenProjectList.java:663)
        at org.netbeans.modules.project.ui.OpenProjectList.access$1200(OpenProjectList.java:122)
        at org.netbeans.modules.project.ui.OpenProjectList$3.run(OpenProjectList.java:553)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:577)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1030)