java.lang.Throwable: Locked by:
   at org.openide.filesystems.FileLock.<init>(FileLock.java:85)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.LockForFile.<init>(LockForFile.java:91)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.LockForFile.tryLock(LockForFile.java:102)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObj.lock(FileObj.java:359)
   at org.openide.filesystems.FileObject.getOutputStream(FileObject.java:736)
Caused: org.openide.filesystems.FileAlreadyLockedException: /tmp/tulach/build.properties
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.LockForFile.registerLock(LockForFile.java:114)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.LockForFile.tryLock(LockForFile.java:103)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObj.lock(FileObj.java:359)
   at org.openide.filesystems.FileObject.getOutputStream(FileObject.java:736)
   at org.netbeans.spi.project.support.ant.PropertyUtils$2.run(PropertyUtils.java:199)
   at org.netbeans.spi.project.support.ant.PropertyUtils$2.run(PropertyUtils.java:167)
   at org.openide.util.Mutex.writeAccess(Mutex.java:438)
   at org.netbeans.spi.project.support.ant.PropertyUtils.putGlobalProperties(PropertyUtils.java:167)
   at org.netbeans.modules.java.j2seplatform.libraries.J2SELibraryTypeProvider$1.run(J2SELibraryTypeProvider.java:140)
   at org.openide.util.Mutex.leaveImpl(Mutex.java:908)
   at org.openide.util.Mutex.leave(Mutex.java:841)
   at org.openide.util.Mutex.readAccess(Mutex.java:292)
   at org.netbeans.spi.project.support.ant.PropertyUtils$FilePropertyProvider.fireChange(PropertyUtils.java:319)
   at org.netbeans.spi.project.support.ant.PropertyUtils$FilePropertyProvider.fileChanged(PropertyUtils.java:350)
   at org.openide.filesystems.FileUtil$Holder.fileChanged(FileUtil.java:505)
   at org.openide.filesystems.FCLSupport$DispatchEventWrapper.dispatchEventImpl(FCLSupport.java:145)
   at org.openide.filesystems.FCLSupport$DispatchEventWrapper.dispatchEvent(FCLSupport.java:128)
   at org.openide.filesystems.FCLSupport.dispatchEvent(FCLSupport.java:105)
   at org.openide.filesystems.FileObject$ED.dispatch(FileObject.java:1246)
   at org.openide.filesystems.FileSystem$EventDispatcher.run(FileSystem.java:997)
   at org.openide.filesystems.EventControl.dispatchEvent(EventControl.java:84)
   at org.openide.filesystems.FileSystem.dispatchEvent(FileSystem.java:642)
   at org.openide.filesystems.FileObject.dispatchEvent(FileObject.java:568)
   at org.openide.filesystems.FileObject.fireFileChangedEvent(FileObject.java:536)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.BaseFileObj.fireFileChangedEvent(BaseFileObj.java:678)
   at org.netbeans.modules.masterfs.filebasedfs.fileobjects.FileObj$1.close(FileObj.java:137)
   at java.io.FilterOutputStream.close(FilterOutputStream.java:160)
   at org.openide.filesystems.FileObject$1.close(FileObject.java:751)
   at org.netbeans.spi.project.support.ant.PropertyUtils$2.run(PropertyUtils.java:203)
   at org.netbeans.spi.project.support.ant.PropertyUtils$2.run(PropertyUtils.java:167)
   at org.openide.util.Mutex.writeAccess(Mutex.java:438)
   at org.netbeans.spi.project.support.ant.PropertyUtils.putGlobalProperties(PropertyUtils.java:167)
   at org.netbeans.modules.java.j2seplatform.libraries.J2SELibraryTypeProvider$1.run(J2SELibraryTypeProvider.java:140)
   at org.openide.util.Mutex.postRequest(Mutex.java:1258)
   at org.openide.util.Mutex.postWriteRequest(Mutex.java:587)
   at org.netbeans.modules.java.j2seplatform.libraries.J2SELibraryTypeProvider.libraryCreated(J2SELibraryTypeProvider.java:132)
   at org.netbeans.modules.project.libraries.LibrariesStorage.loadFromStorage(LibrariesStorage.java:176)
   at org.netbeans.modules.project.libraries.LibrariesStorage.initStorage(LibrariesStorage.java:222)
   at org.netbeans.modules.project.libraries.LibrariesStorage.getLibraries(LibrariesStorage.java:292)
   at org.netbeans.api.project.libraries.LibraryManager.getLibraries(LibraryManager.java:226)
   at org.netbeans.modules.java.j2seplatform.libraries.J2SELibraryClassPathProvider.findClassPath(J2SELibraryClassPathProvider.java:91)
   at org.netbeans.api.java.classpath.ClassPath.getClassPath(ClassPath.java:628)
   at org.netbeans.modules.java.JavaNode$ExecutableTask.run(JavaNode.java:386)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1452)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2032)