Cannot find java. Please use the --jdkhome switch.

[ian-carolan]

nbRsync 26.03 linux version.

Error on launch:

bash /opt/nbrsync/bin/nbrsync
Cannot find java. Please use the --jdkhome switch.

Using openSUSE Tumbleweed with java at /usr/bin/java and using java located at /opt/nbrsync/jre/bin/java.
I tried all combinations of --jdkhome switch including the nbrsync conf, file but cannot get it to run.

Version 24.12 is the last version that worked for me.

[trixon]

Hi @ian-carolan ,
Did you do a manual download that you unzipped and move to opt?
Do you get the same result if you try do run the unzipped download without moving it first?
--jdkhome should be used like
--jdkhome /path/to/jre_with_javafx

[ian-carolan]

I downloaded the zip manually then created /opt/nbrsync folder then unzipped contents of zip into created folder.

Same result without moving it first with extra warning:

Detected KDE; use explicit setting for font antialiasing (-J-Dawt.useSystemAAFontSettings=lcd_hrgb)
Cannot find java. Please use the --jdkhome switch.

I have tried every combination of paths I can think of but I always get the same error.
Can you provide an example of the --jdkhome switch path given it is in /opt/nbrsync?

As stated 24.12 is the last version that works for me. So something has obviously changed as I assume the program should use its internal java runtime?

[trixon]

In your first example, I would use
nbrsync --jdkhome /opt/nbrsync/jre

I think the path in the nbrsync.conf only supports relative paths to the nbrsync base directory.
You could try to comment that line out, then it would try to use your default java, unless you specify a jdkhome.

[ian-carolan]

Thank you for your replies.

nbrsync --jdkhome /opt/nbrsync/jre
produces:
Detected KDE; use explicit setting for font antialiasing (-J-Dawt.useSystemAAFontSettings=lcd_hrgb) java.lang.NoClassDefFoundError: org/netbeans/TopSecurityManager at org.netbeans.core.NbLifecycleManager.advancePolicy(NbLifecycleManager.java:69) at org.netbeans.core.GuiRunLevel.run(GuiRunLevel.java:84) at org.netbeans.core.startup.Main.start(Main.java:316) at org.netbeans.core.startup.TopThreadGroup.run(TopThreadGroup.java:98) at java.base/java.lang.Thread.run(Unknown Source) Caused by: java.lang.ClassNotFoundException: org.netbeans.TopSecurityManager starting from ModuleCL@55395063[org.netbeans.core] with possible defining loaders null and declared parents [org.netbeans.JarClassLoader@c65deaf, ModuleCL@6a4fc985[org.openide.windows], ModuleCL@5d72faa3[org.openide.awt], ModuleCL@4d794123[org.openide.explorer], org.netbeans.MainImpl$BootClassLoader@6e0e048a, ModuleCL@7459cf7[org.openide.nodes], ModuleCL@4d06e98a[org.openide.actions], ModuleCL@2794d43[org.netbeans.modules.sampler], ModuleCL@4b0dac7e[org.openide.loaders], ModuleCL@1cbf56d2[org.openide.io], ...3 more] at org.netbeans.ProxyClassLoader.doFindClass(ProxyClassLoader.java:226) at org.netbeans.ProxyClassLoader.loadClass(ProxyClassLoader.java:140) at java.base/java.lang.ClassLoader.loadClass(Unknown Source) ... 5 more Caused by: java.lang.ClassNotFoundException: org.netbeans.TopSecurityManager at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(Unknown Source) at java.base/java.lang.ClassLoader.loadClass(Unknown Source) at org.netbeans.ProxyClassLoader.doFindClass(ProxyClassLoader.java:224) ... 7 more

and the program is displayed but menu options are non functional .
If I can be any more help Troubleshooting let me know.

[trixon]

At this point I suspect something is messed up in your user and/or cache dir.
Try something like
nbrsync --userdir /tmp/nbr88 --cachedir /tmp/nbr99
along with your --jdkhome.

You can also move/remove ~/.nbrsync and ~/.cache/nbrsync and then you don't have to specify new userdir & cachedir.

[ian-carolan]

I have removed the folders you recommended and started nbrsync using
nbrsync --jdkhome /opt/nbrsync/jre
This produces a dialog window asking to "Disable Modules to Continue or Exit".
I chose Exit for the time being.

Here is a screenshot of the dialog window:

I do not know if disabling modules is something I should do.

[trixon]

That indicates that you are trying to start nbrsync with java 23 when it requires java 25 (with javafx modules).

[ian-carolan]

On openSuSE tumbleweed (a rolling release distro) my local java --version is:

$ java --version
openjdk 25.0.2 2026-01-20
OpenJDK Runtime Environment (build 25.0.2+10-suse-1699-x8664)
OpenJDK 64-Bit Server VM (build 25.0.2+10-suse-1699-x8664, mixed mode, sharing)

and

$ whereis java
java: /usr/bin/java /usr/lib64/java /etc/java /usr/share/java

openjfx version: 17.0.18.0-1.1

I thought that nbrsync --jdkhome /opt/nbrsync/jre would run the nbrsync internal version of the jre?
I'm confused. Do you have any suggestions?

[trixon]

This sounds really strange.

What's the output of
/opt/nbrsync/jre/bin/java --version

When you update nbrsync you sould clear/remove /opt/nbrsync or create dir versions like /opt/nbrsync2603
since just copying new content to an existing dir will cause problems.

[ian-carolan]

Damn!

$ /home/opt/nbrsync-new/jre/bin/java --version
bash: /home/opt/nbrsync-new/jre/bin/java: Permission denied

setting 0775 permissions on nbrsync-new fixed the problem.

Thank you for your patience and help.
How can i star your project, my old brain is new to this github stuff?

[trixon]

Great news!
Regarding the star I guess you just click on the star in the upper right corner. :)