NullPointerException When publishing report book

[byron.ullauri]

Created a report book using 'wave' as a base template for its table of contents. During publishing, when looking for resources used (subreports in my case), I get an error with the following details

java.lang.NullPointerException
    at com.jaspersoft.studio.server.publish.JrxmlPublishContributor.publishParts(JrxmlPublishContributor.java:135)
    at com.jaspersoft.studio.server.publish.JrxmlPublishContributor.publishJrxml(JrxmlPublishContributor.java:120)
    at com.jaspersoft.studio.server.publish.JrxmlPublishContributor.publishJrxml(JrxmlPublishContributor.java:76)
    at com.jaspersoft.studio.server.publish.FindResources.findResources(FindResources.java:98)
    at com.jaspersoft.studio.server.publish.FindResources.find(FindResources.java:40)
    at com.jaspersoft.studio.server.publish.wizard.Publish2ServerWizard$2.run(Publish2ServerWizard.java:259)
    at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:437)
    at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:353)
    at org.eclipse.jface.wizard.WizardDialog.run(WizardDialog.java:993)
    at com.jaspersoft.studio.server.publish.wizard.Publish2ServerWizard.doFindDependentResources(Publish2ServerWizard.java:255)
    at com.jaspersoft.studio.server.publish.wizard.Publish2ServerWizard$1$1.run(Publish2ServerWizard.java:205)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:182)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4032)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3708)
    at org.eclipse.jface.window.Window.runEventLoop(Window.java:818)
    at org.eclipse.jface.window.Window.open(Window.java:794)
    at com.jaspersoft.studio.server.publish.action.JrxmlPublishAction.publishReportUnit(JrxmlPublishAction.java:132)
    at com.jaspersoft.studio.server.publish.action.JrxmlPublishAction$2.run(JrxmlPublishAction.java:94)
    at org.eclipse.ui.internal.UILockListener.doPendingWork(UILockListener.java:162)
    at org.eclipse.ui.internal.UISynchronizer$3.run(UISynchronizer.java:154)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:182)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4032)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3708)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1121)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1022)
    at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:150)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:693)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:610)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
    at com.jaspersoft.studio.rcp.intro.Application.start(Application.java:91)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:673)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:610)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1519)
 

Tried publishing the same 'wave' sample report book and was successful. 

[byron.ullauri]

Solved this by removing a subreport I had in the 'BackCover' section of the report book.

Not entirely sure why that was causing an issue, but when rebuilding the report book part by part having the subreport there raised NullPointerException.