Gfilui

After fresh Ubuntu 18.04 installation and afterwards a netbeans installation, netbeans does not start. netbeans was installed with

sudo apt install netbeans

some other java programms (at least Eclipse) do not start too.

when starting netbeans from commandline the JVM prints folowing WARNINGS:

➜ ~ netbeans
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.netbeans.ProxyURLStreamHandlerFactory (file:/usr/share/netbeans/platform18/lib/boot.jar) to field java.net.URL.handler
WARNING: Please consider reporting this to the maintainers of org.netbeans.ProxyURLStreamHandlerFactory
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
➜ ~ 

Your question made me recheck my Netbeans and I found the same issue but I somehow resolved it.

Ubuntu's repository still has Netbeans 8.1 but JDK 11. So I've downloaded Netbeans 8.2 from Netbeans Website

After downloading Netbeans 8.2, follow these steps:

sudo apt autoremove netbeans
cd Downloads
sudo chmod +x netbeans-8.2-linux.sh
./netbeans-8.2-linux.sh

and follow on screen instructions. Import settings and launch the netbeans from app drawer.

Also if you have any package with name as JDK 8, just remove it. You can find the packages installed by using

sudo apt list --installed

and remove all packages with name as openjdk-8- by using,

sudo apt autoremove <package_name>

Let me know if this helps. :)

I was able to solve this by running sudo update-alternatives --config java and then selecting the java-8 option rather than the default java-11. You will need to have the java-8 openjdk package still installed for this to work though.

I am having the same issue running on 18.04.1 mate. netbeans installed from apt.

> mulawa@mike-VirtualBox:~$ netbeans --help Usage:
> /usr/share/netbeans/8.1/platform/lib/nbexec options arguments
> 
> General options: --help show this help --jdkhome
> <path> path to Java(TM) 2 SDK, Standard Edition -J<jvm_option> 
> pass <jvm_option> to JVM
> 
> --cp:p <classpath> prepend <classpath> to classpath --cp:a
> <classpath> append <classpath> to classpath WARNING: An illegal
> reflective access operation has occurred WARNING: Illegal reflective
> access by org.netbeans.ProxyURLStreamHandlerFactory
> (file:/usr/share/netbeans/platform18/lib/boot.jar) to field
> java.net.URL.handler WARNING: Please consider reporting this to the
> maintainers of org.netbeans.ProxyURLStreamHandlerFactory WARNING: Use
> --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be
> denied in a future release Exception in thread "main"
> java.awt.AWTError: Assistive Technology not found:
> org.GNOME.Accessibility.AtkWrapper at
> java.desktop/java.awt.Toolkit.newAWTError(Toolkit.java:472) at
> java.desktop/java.awt.Toolkit.fallbackToLoadClassForAT(Toolkit.java:488)
> at
> java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
> at
> java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
> at
> java.base/java.util.HashMap$KeySpliterator.forEachRemaining(HashMap.java:1608)
> at
> java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
> at
> java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
> at
> java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
> at
> java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
> at
> java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
> at
> java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
> at
> java.desktop/java.awt.Toolkit.loadAssistiveTechnologies(Toolkit.java:532)
> at java.desktop/java.awt.Toolkit.getDefaultToolkit(Toolkit.java:613)
> at java.desktop/java.awt.Toolkit.getEventQueue(Toolkit.java:1494) at
> java.desktop/java.awt.EventQueue.invokeLater(EventQueue.java:1312) at
> java.desktop/javax.swing.SwingUtilities.invokeLater(SwingUtilities.java:1421)
> at org.netbeans.core.startup.Splash$SplashPainter.setText(Unknown
> Source) at org.netbeans.core.startup.Splash.print(Unknown Source) at
> org.netbeans.core.startup.Main.setStatusText(Unknown Source) at
> org.netbeans.core.startup.layers.LayerCacheManager.loadCache(Unknown
> Source) at
> org.netbeans.core.startup.layers.ModuleLayeredFileSystem.<init>(Unknown
> Source) at
> org.netbeans.core.startup.layers.SystemFileSystem.createInstallHomeSystem(Unknown
> Source) at
> org.netbeans.core.startup.layers.SystemFileSystem.create(Unknown
> Source) at
> org.netbeans.core.startup.layers.SessionManager.create(Unknown Source)
> at
> org.netbeans.core.startup.NbRepository.createDefaultFileSystem(Unknown
> Source) at org.netbeans.core.startup.NbRepository.<init>(Unknown
> Source) at
> java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native
> Method) at
> java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
> at
> java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
> at
> java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488)
> at java.base/java.lang.Class.newInstance(Class.java:560) at
> org.openide.util.lookup.implspi.SharedClassObjectBridge.newInstance(Unknown
> Source) at
> org.openide.util.lookup.MetaInfServicesLookup$Item.getInstance(Unknown
> Source) at org.openide.util.lookup.AbstractLookup.lookup(Unknown
> Source) at org.openide.util.lookup.ProxyLookup.lookup(Unknown Source)
> at org.openide.filesystems.Repository$3.call(Unknown Source) at
> org.openide.filesystems.Repository$3.call(Unknown Source) at
> org.openide.filesystems.Repository.delayFileSystemAttachImpl(Unknown
> Source) at org.openide.filesystems.Repository.getDefault(Unknown
> Source) at org.openide.filesystems.Repository$4.getRepository(Unknown
> Source) at
> org.openide.filesystems.Repository.getLocalRepository(Unknown Source)
> at org.openide.filesystems.FileUtil.getConfigFile(Unknown Source) at
> org.openide.filesystems.FileUtil.getConfigRoot(Unknown Source) at
> org.netbeans.core.startup.CLICoreBridge.usage(Unknown Source) at
> org.netbeans.CLIHandler.showHelp(Unknown Source) at
> org.netbeans.CLIHandler.checkHelp(Unknown Source) at
> org.netbeans.CLIHandler.initialize(Unknown Source) at
> org.netbeans.CLIHandler.initialize(Unknown Source) at
> org.netbeans.MainImpl.execute(Unknown Source) at
> org.netbeans.MainImpl.main(Unknown Source) at
> org.netbeans.Main.main(Unknown Source) Caused by:
> java.lang.ClassNotFoundException: org.GNOME.Accessibility.AtkWrapper
> at
> java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
> at
> java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190)
> at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
> at java.base/java.lang.Class.forName0(Native Method) at
> java.base/java.lang.Class.forName(Class.java:374) at
> java.desktop/java.awt.Toolkit.fallbackToLoadClassForAT(Toolkit.java:485)
> ... 49 more

and simillar error entry in log when installing from downloaded .sh file:

> java.awt.AWTError: Assistive Technology not found: org.GNOME.Accessibility.AtkWrapper
> (...)
> Caused by: java.lang.ClassNotFoundException: org.GNOME.Accessibility.AtkWrapper

so if i read correctly, netbeans requires gnome even on different display manager?

EDIT:
this helped a little: https://askubuntu.com/a/723503/603947