Can't run OpenRocket on linux

[OZ1SEJ]

I have Ubuntu 18.04. The guide on https://wiki.openrocket.info/Downloading_&_Installing says to install using

$ sudo apt install openrocket

which I did. This seems to have gone okay, except for

head: can't open '/etc/ssl/certs/java/cacerts' for reading: No such file or directory

and

downloading navbar_download_button
https://github.com/openrocket/openrocket/releases/download/release-15.03/OpenRocket-15.03.jar...
--2019-01-31 12:21:26--  https://navbar_download_button/
Resolving navbar_download_button (navbar_download_button)... failed: Name or service unknown.
wget: can't resolve host address 'navbar_download_button'

and

ERROR: wget failed to download

The guide now says "To start OpenRocket, simply select it from the Applications menu." Which I can't, since it's not in my applications menu.

Now, since this didn't work, I just downloaded the jar file. But when I run

$ java -jar OpenRocket-15.03.jar

I get this:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$2 (file:/home/steen/Programmer/OpenRocket-15.03.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$2
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

I tried to file a bug report, but the bug reporting tool returns 404. Running it with sudo gives the same result.

Please help if you can.

 

[Tobor]

This may help

Ask Ubuntu - Java can't find cacerts (Link)

 

[dhbarr]

The first set of issues is known; bdale's installer package scrapes sourceforge which no longer works.

For the second, what version of Java? I suspect that warning can be surpressec, or an older Java installed.

 

[OZ1SEJ]

The first set of issues is known; bdale's installer package scrapes sourceforge which no longer works.

For the second, what version of Java? I suspect that warning can be surpressec, or an older Java installed.

openjdk version "10.0.2" 2018-07-17
OpenJDK Runtime Environment (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4)
OpenJDK 64-Bit Server VM (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4, mixed mode)

 

[dhbarr]

If you choose to install Java 8 and set it default:

# install not-oracle Java 8
sudo apt install openjdk-8-jdk

# set the one we just installed as default
sudo update-alternatives --config java

 

[OZ1SEJ]

So you're saying I should install Java 8 and use that to run OpenRocket? Would that work? Would this impact other Java programs I run on my computer? Can this be (easily) undone, if it doesn't work?

 

[dhbarr]

So you're saying I should install Java 8 and use that to run OpenRocket? Would that work? Would this impact other Java programs I run on my computer? Can this be (easily) undone, if it doesn't work?

If you choose to.

Maybe.

Possibly.

Yes, it's about as hard to undo as it is to do.

 

[plugger]

Hi OZ1SEJ,

You don't need to set Java 8 as your default to run OpenRocket. Instead you can just explicitly use the path for the older version of Java to run up OR. I had the same error as you and looked at dhbarr's comment of changing the version of Java.

$sudo update-alternatives --config java
There are 4 choices for the alternative java (providing /usr/bin/java).

Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/lib/jvm/java-11-openjdk-amd64/bin/java 1111 auto mode
1 /usr/lib/jvm/java-10-openjdk-amd64/bin/java 1101 manual mode
2 /usr/lib/jvm/java-11-openjdk-amd64/bin/java 1111 manual mode
3 /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java 1081 manual mode
4 /usr/lib/jvm/java-9-openjdk-amd64/bin/java 1091 manual mode

You can see the Java 8 executable is in the path /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java.

So cd to that directory and run the following command.

USER@HOST:/usr/lib/jvm/java-8-openjdk-amd64/jre/bin$ ./java -jar /<full path to the OR jar file>/OpenRocket-15.03.jar

And that should work. It did for me. And if you don't have Java 8 on your box install it with the command dhbarr provided above. It shouldn't impact any of your other java apps as long as you don't change your default version of java from the symlink in /usr/bin/java.

Cheers,

Andrew

 

[OZ1SEJ]

It works! Thanks for your help - all of you