Scilab is unable to start due to "Could not access to the Main Scilab Class"

[Norbert]

Steps to reproduce:
1. Have Ubuntu 16.04 LTS installed
2. Install Scilab package with simple `sudo apt-get install scilab`
3. Launch Scilab from terminal with `scilab`

Expected result:
* Scilab starts and shows GUI

Actual result:
* Scilab does not start and do not show GUI, only error message in the terminal:

$ scilab
Could not access to the Main Scilab Class:
Exception in thread "main" java.lang.ExceptionInInitializerError
 at org.scilab.modules.localization.Messages.gettext(Unknown Source)
 at org.scilab.modules.commons.xml.XConfiguration.<clinit>(Unknown Source)
 at org.scilab.modules.core.Scilab.<clinit>(Unknown Source)
Caused by: java.lang.NullPointerException
 at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1847)
 at java.lang.Runtime.loadLibrary0(Runtime.java:871)
 at java.lang.System.loadLibrary(System.java:1124)
 at org.scilab.modules.localization.MessagesJNI.<clinit>(Unknown Source)
 ... 3 more

Scilab cannot create Scilab Java Main-Class (we have not been able to find the main Scilab class. Check if the Scilab and thirdparty packages are available).

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: scilab 5.5.2-2ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-174.204-generic 4.4.211
Uname: Linux 4.4.0-174-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.21
Architecture: amd64
CurrentDesktop: MATE
Date: Tue Feb 18 12:25:50 2020
InstallationDate: Installed on 2019-05-07 (287 days ago)
InstallationMedia: Ubuntu-MATE 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
PackageArchitecture: all
SourcePackage: scilab
UpgradeStatus: No upgrade log present (probably fresh install)

[Norbert (nrbrtx)]

Installing OpenJDK from main fixes the issue:

```
sudo apt-get install openjdk-8-jre:amd64=8u77-b03-3ubuntu3 openjdk-8-jre-headless:amd64=8u77-b03-3ubuntu3

cat <<EOF | sudo tee /etc/apt/preferences.d/pin-java-scilab
Package: openjdk-8-jre:amd64
Pin: version 8u77-b03-3ubuntu3
Pin-Priority: 1337

Package: openjdk-8-jre-headless:amd64
Pin: version 8u77-b03-3ubuntu3
Pin-Priority: 1337
EOF
```

So new OpenJDK breaks Scilab.

[Norbert (nrbrtx)]

Other solution is to use 232:

```
cd ~/Downloads
wget https://launchpadlibrarian.net/446930389/openjdk-8-jre_8u232-b09-0ubuntu1~16.04.1_amd64.deb
wget https://launchpadlibrarian.net/446930388/openjdk-8-jre-headless_8u232-b09-0ubuntu1~16.04.1_amd64.deb

sudo apt-get install ./openjdk-8-jre_8u232-b09-0ubuntu1~16.04.1_amd64.deb ./openjdk-8-jre-headless_8u232-b09-0ubuntu1~16.04.1_amd64.deb

cat <<EOF | sudo tee /etc/apt/preferences.d/pin-java-scilab
Package: openjdk-8-jre:amd64
Pin: version 8u232-b09-0ubuntu1~16.04.1
Pin-Priority: 1337

Package: openjdk-8-jre-headless:amd64
Pin: version 8u232-b09-0ubuntu1~16.04.1
Pin-Priority: 1337
EOF
```

[One sapien (onesapien-deactivatedaccount)]

I have the same bug in Ubuntu 20.04.1 LTS.