java.lang.IllegalArgumentException: Already listening to /home/vriha/NetBeansProjects/HTML5Application16/public_html
   at org.openide.filesystems.FileUtil.addFileChangeListener(FileUtil.java:291)
   at org.openide.filesystems.FileUtil.addRecursiveListener(FileUtil.java:410)
   at org.openide.filesystems.FileUtil.addRecursiveListener(FileUtil.java:337)
   at org.netbeans.modules.web.clientproject.ClientSideProject$OpenHookImpl.addSiteRootListener(ClientSideProject.java:451)
   at org.netbeans.modules.web.clientproject.ClientSideProject$OpenHookImpl.projectOpened(ClientSideProject.java:429)
   at org.netbeans.spi.project.ui.ProjectOpenedHook$1.projectOpened(ProjectOpenedHook.java:84)
   at org.netbeans.modules.project.ui.OpenProjectList.notifyOpened(OpenProjectList.java:1217)
   at org.netbeans.modules.project.ui.OpenProjectList.doOpenProject(OpenProjectList.java:1298)
   at org.netbeans.modules.project.ui.OpenProjectList.open(OpenProjectList.java:790)
   at org.netbeans.modules.project.ui.OpenProjectList$5.run(OpenProjectList.java:658)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1454)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2036)