Issue with permissions (classes_nocoops.jsa)

[alcides]

Relevant context:

This happens in a university setting, where all machines are running stock ubuntu 24.04.3 LTS. However, the homedir of every user is mounted from a server and, because of that, we cannot change the permissions of any file in the homedir (Every file is 755).

When installing the Java extension, it fails with the following error message:

2025-11-07 14:25:07.180 [error] [Window] Error: EACCES: permission denied, open '/home/ALUNOSFC/pes000/.vscode/extensions/.29c2353e-6605-4e6f-9a0f-0ebaa25de2d4/jre/21.0.8-linux-x86_64/lib/server/classes_nocoops.jsa'
2025-11-07 14:25:07.199 [error] [Window] EACCES: permission denied, open '/home/ALUNOSFC/pes000/.vscode/extensions/.29c2353e-6605-4e6f-9a0f-0ebaa25de2d4/jre/21.0.8-linux-x86_64/lib/server/classes_nocoops.jsa': Error: EACCES: permission denied, open '/home/ALUNOSFC/pes000/.vscode/extensions/.29c2353e-6605-4e6f-9a0f-0ebaa25de2d4/jre/21.0.8-linux-x86_64/lib/server/classes_nocoops.jsa'

It is not clear to me what is the role of the non-default permissions of this file. Is it possible for this class not to require different permissions?

[fbricon]

Mmm on my Mac the file has 444 permissions

-r--r--r-- 1 fbricon staff 13M Nov 3 11:46 classes_nocoops.jsa

you could try to either:

• disable App CDS (java.jdt.ls.appcds.enabled)
• point to a different local JDK (java.jdt.ls.java.home) (Java 21+)
• if the issue really happens during installation, not on startup, then install the universal vsix, which doesn't embed the JDK,

[fbricon]

@alcides care to share how you resolved this?

[alcides]

The universal vsix worked in our scenario, since we already had an JDK (21) installed on those machines.

Thank you so much for the help.