Connect to openoffice database fails

Help
1

I’m running JabRef v. 4.3.1 on Linux platform with Oracle java version 1.8.0_201. And I’d like to connect to LibreOffice (LO) Bibliographic database.Both connection methods automatic and manual fails with error:
java.io.IOException: (Not all) required Open Office Jars were found inside installation path.
I’ve made a symlink in /opt/openoffice4 with the following content:
CREDITS.fodt help LICENSE LICENSE.fodt LICENSE.html NOTICE presets program share
And the LO java libraries are seems to be installed in to directory ls /opt/openoffice4/program/classes/ These files are:
commonwizards.jar java_uno.jar jurt.jar reportbuilderwizard.jar ScriptFramework.jar sdbc_hsqldb.jar unoil.jar xmerge.jar form.jar js.jar query.jar report.jar ScriptProviderForJava.jar smoketest.jar unoloader.jar hsqldb.jar juh.jar reportbuilder.jar ridl.jar ScriptProviderForJavaScript.jar table.jar XMergeBridge.jar
With manual connection I was trying to provide the following paths:
/opt/openoffice4/program/classes/
/opt/openoffice4/program
/opt/openoffice4
No succes. What am I doing wrong?

Many thx in advance.
p.s. Java runtime environment activated in LO by clicking a checkbox in Otions-Advanced frame.

2

Update: It seems to work in my other laptop computer, with Java 1.8.0_181. So, probably I need to downgrade the java in my office computer, will et you know AFAP.

3

Update2: OK, I’ve downgade the oracle jre, and I’ve found that open-jdk was installed, wich I removed also. Finally I’ve removed all previous jabref cache and configurashion files with command:
rm -rf ~/.java/.userPrefs/org/jabref
And this made a trick. Nice feature after all and it works finally. The problem is resolved.