Problem with uninstalling java

Question

To uninstall java I followed this.

When I have uninstalled java completely , java -version shows openjdk version "11.0.1" . It's supposed to be no java at all, isn't it?.

Then I've installed java 8, still java -version command yields openjdk version "11.0.1".

I need java for running a bioinformatics tool called Integrative Genomics Viewer(igv). After installing java 8 it continues to tell me I need java 8.

Please help.

I've used update-alternatives while both java 11 and java 8 were installed. But it didn't work so I decided to completely uninstall the java and only use java 8 (which I need at the moment). — Ahmed Abdullah, Dec 27 '18 at 07:18
@Kulfy apt list --installed | grep jdk returns "WARNING: apt does not have a stable CLI interface. Use with caution in scripts." and no other result — Ahmed Abdullah, Dec 27 '18 at 07:25
With java, you don't use update-alternatives but update-java-alternatives as I described here. — danzel, Dec 27 '18 at 09:53
@danzel I followed your answer https://askubuntu.com/a/740782/814468 before I tried removing java. It didn't work. Somehow I am stuck with java version 11 even when no java is installed apparently. — Ahmed Abdullah, Dec 27 '18 at 09:56
How did you installed java 8? Also, which command usually returns path of executable file. Are you sure that is the output of which java and which javac? — Kulfy, Dec 27 '18 at 10:05
for java 8 installation I followed commands provided by this page http://tipsonubuntu.com/2016/07/31/install-oracle-java-8-9-ubuntu-16-04-linux-mint-18/ — Ahmed Abdullah, Dec 27 '18 at 10:12
There is no need to follow those instructions unless you need oracle JDK. For installing JDK 8 you can simply use sudo apt install openjdk-8-jre openjdk-8-jdk since they are present in official repository. Let me know if it overwrites the existing settings. — Kulfy, Dec 27 '18 at 10:32
And what about apt list --installed | grep jre? I'll suggest you to install openjdk-11 from repository once again using sudo apt install openjdk-11-jdk openjdk-11-jre and uninstall using sudo apt autoremove openjdk-11-jdk openjdk-11-jre to get of its all traces. — Kulfy, Dec 28 '18 at 13:57

score 2 · Answer 1 · edited Jan 01 '19 at 18:38

The IGV program started for me, these were the steps I took:

I uninstalled my version of Java and installed Java 8.

$ java -version
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)

$ sudo apt remove openjdk*

$ java -version
bash: /usr/bin/java: No such file or directory

$ sudo apt update

$ sudo apt install openjdk-8-jdk

$ java -version
openjdk version "1.8.0_191"
OpenJDK Runtime Environment (build 1.8.0_191-8u191-b12-0ubuntu0.18.04.1-b12)
OpenJDK 64-Bit Server VM (build 25.191-b12, mixed mode)

$ cd  Downloads/IGV_2.4.16
~/Downloads/IGV_2.4.16 $ ls
igv.command  igv.sh  lib  readme.txt

$ chmod a+x igv.sh  //Made the script executable
$ ./igv.sh  //Execute the script and start the program.

Hope this works for you.

score 0 · Answer 2 · answered Dec 27 '18 at 09:26

0

Sounds like you did not delete openjdk if it's still listed. Try running sudo apt-get purge --auto-remove openjdk* to remove the unsupported version of java, then install java 8.

answered Dec 27 '18 at 09:26

Jonathan Fetzer

21

It doesn't work. 'java -version' command still yields openjdk version "11.0.1" – Ahmed Abdullah Dec 27 '18 at 09:59

Problem with uninstalling java

2 Answers2