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Stack trace

javax.servlet.ServletException: java.lang.NullPointerException
	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:726)
	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:777)
	at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:239)
	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:684)
	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:777)
	at org.kohsuke.stapler.Stapler.invoke(Stapler.java:586)
	at org.kohsuke.stapler.Stapler.service(Stapler.java:217)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
	at winstone.ServletConfiguration.execute(ServletConfiguration.java:248)
	at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:376)
	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:96)
	at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:208)
	at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:181)
	at net.bull.javamelody.PluginMonitoringFilter.doFilter(PluginMonitoringFilter.java:86)
	at org.jvnet.hudson.plugins.monitoring.HudsonMonitoringFilter.doFilter(HudsonMonitoringFilter.java:84)
	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:99)
	at hudson.plugins.audit_trail.AuditTrailFilter.doFilter(AuditTrailFilter.java:66)
	at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:99)
	at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:88)
	at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
	at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:48)
	at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
	at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:118)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:174)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at jenkins.security.ApiTokenFilter.doFilter(ApiTokenFilter.java:64)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
	at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)
	at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
	at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
	at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
	at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
	at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:47)
	at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
	at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
	at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
	at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
	at winstone.RequestDispatcher.forward(RequestDispatcher.java:331)
	at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:227)
	at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
	at java.util.concurrent.FutureTask.run(FutureTask.java:138)
	at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.NullPointerException
	at net.hurstfrost.hudson.sounds.HudsonSoundsNotifier$HudsonSoundsDescriptor.doCheckSoundArchive(HudsonSoundsNotifier.java:423)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:297)
	at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:160)
	at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:95)
	at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:111)
	at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:53)
	at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:684)
	... 63 more

uri.getScheme().equals("file")

"file".equals(uri.getScheme())