Introduction

After checking your Java Environment, downloaded and installed either an Oracle JDK or an Open JDK, now it's time to pack everything together.

At this point, you have a JVM installed below your /usr/lib/jvm directory and you've a jinfo file tuned to your needs with a unique priority number.

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Install Install

Install

Now it's time to link /etc/alternatives with our new installed JVM. 

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InstallCommandLine InstallCommandLine

Command Line

Usually one has to install each java commands, tools or libraries one by one with the following interactive command:

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sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/default-java/jre/bin/java" 1073;

Check if your added JVM java command has been processed by running:

user@machine:~$ update-alternatives --list java
/usr/lib/jvm/default-java/jre/bin/java
/usr/lib/jvm/java-8-openjdk-i386/jre/bin/java
/usr/lib/jvm/java-8-oracle/jre/bin/java
/usr/lib/jvm/ramdisk-java-8-oracle/jre/bin/java

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InstallScripting InstallScripting

Scripting

Doing this task one by one is pretty tedious, we provide a shell script ito facilitate the work.

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It means that ramdisk-java-8-oracle should be installed through the Update Alternatives mechanism before we can set the alternatives to default-java or you define a jinfo file with a different priority number.

Then check again that everything is correct with your Java Update Alternatives Environment.

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Uninstall Uninstall

Uninstall

Now it's time to unlink /etc/alternatives with the JVM we want to uninstall. 

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UninstallCommandLine UninstallCommandLine

Command Line

Usually one has to uninstall each java commands, tools or libraries one by one with the following interactive command:

sudo update-alternatives --remove "java" "/usr/lib/jvm/default-java/jre/bin/java";

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UninstallScripting UninstallScripting

Scripting

Doing this task one by one is pretty tedious, we provide a shell script ito facilitate the work.

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