Pb of installation LanguageTool - 3.6 on LibreOffice Version: 5.1.4.2

Hello everybody,
I tried to install
—>LanguageTool - 3.6 extension
on my LibreOffice Version: 5.1.4.2 but I got a little problem with a beautiful Java sent back by the extension manager of LibreOffice (version: 5.1.4.2)
—> I got a “RuntimeException” that occurred during a registration due to a calling method “writeRegistryInfo” of UNO that seems not to exist.
Since I am not an expert of the architecture of LibreOffice, many thanks if you could help me regarding this little problem.

The Java compiler I use on my distribution “Ubuntu 16.04” is an OpenJdk:
java -version
openjdk version “1.8.0_121”
OpenJDK Runtime Environment (build 1.8.0_121-8u121-b13-0ubuntu1.16.04.2-b13)
OpenJDK 64-Bit Server VM (build 25.121-b13, mixed mode)

Many thanks for your help by advance.
Cordially.
Bye
Marc

The stack trace of the Java error is below:
(com.sun.star.uno.RuntimeException) { { Message = “[jni_uno bridge error] UNO calling Java method writeRegistryInfo: non-UNO exception occurred: java.lang.NoClassDefFoundError: com/sun/star/task/XJobExecutor\X000ajava stack trace:\X000ajava.lang.NoClassDefFoundError: com/sun/star/task/XJobExecutor\X000a\X0009at java.lang.ClassLoader.defineClass1(Native Method)\X000a\X0009at java.lang.ClassLoader.defineClass(ClassLoader.java:763)\X000a\X0009at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)\X000a\X0009at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)\X000a\X0009at java.net.URLClassLoader.access$100(URLClassLoader.java:73)\X000a\X0009at java.net.URLClassLoader$1.run(URLClassLoader.java:368)\X000a\X0009at java.net.URLClassLoader$1.run(URLClassLoader.java:362)\X000a\X0009at java.security.AccessController.doPrivileged(Native Method)\X000a\X0009at java.net.URLClassLoader.findClass(URLClassLoader.java:361)\X000a\X0009at java.lang.ClassLoader.loadClass(ClassLoader.java:424)\X000a\X0009at java.lang.ClassLoader.loadClass(ClassLoader.java:411)\X000a\X0009at java.net.FactoryURLClassLoader.loadClass(URLClassLoader.java:814)\X000a\X0009at java.lang.ClassLoader.loadClass(ClassLoader.java:357)\X000a\X0009at com.sun.star.comp.loader.RegistrationClassFinder.find(RegistrationClassFinder.java:52)\X000a\X0009at com.sun.star.comp.loader.JavaLoader.writeRegistryInfo(JavaLoader.java:380)\X000aCaused by: java.lang.ClassNotFoundException: com.sun.star.task.XJobExecutor\X000a\X0009at java.net.URLClassLoader.findClass(URLClassLoader.java:381)\X000a\X0009at java.lang.ClassLoader.loadClass(ClassLoader.java:424)\X000a\X0009at java.lang.ClassLoader.loadClass(ClassLoader.java:357)\X000a\X0009… 15 more\X000a”, Context = (com.sun.star.uno.XInterface) @0 } }

Hello everybody,

After having a look on the home site:
—>[https://www.languagetool.org/issues/]
and then after go to the Chapter below of the page of the URL above :
------->Common Problems with LibreOffice/OpenOffice.org Integration
I have finally found the answer to my problem.

Since the Ubuntu distribution doesn’t seem to have include the library “libreoffice-java-common” in the LibreOffice package,you have to do that by yourself.
For that, you have to go to URL below:
------->[UbuntuUpdates - Package "libreoffice-java-common" (xenial 16.04)]

This package “libreoffice-java-common” is necessary to enable LibreOffice to use the Java VM.
If this package is missing then LibreOffice can’t use Java.

After an apt-get command to install this missing package, then “LanguageTool” works perfectly.

Sorry for the disturb.
Things were not so complicated to solve, you have only to look at the right place on the net.

Cordially
Bye
Marc