how to setup java-1_8_0-openjdk-devel after installation ?

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1

Hello i have installed java-1_8_0-openjdk-devel via yast in openSUSE Leap 42.1 , now how do i install and set it up as the system default(like for java,javac,jar,javaws etc.) and also use java-1_8_0-openjdk-plugin for the browser plugin by using update-alternatives ?( how to install the respective firefox plugin ?)
This is the current addon i can see in firefox- IcedTea-Web Plugin (using IcedTea-Web 1.6.1 (suse-1.2-x86_64))

These are my current configs - As you can see there are only jre* options in --config java and there are lot of java-1_8_0-openjdk* folders in /usr/lib64/jvm/) . Please help on how to proceed from here, planning to use tools like android studio, Intellij IDEA etc…


update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                       Priority   Status
------------------------------------------------------------
* 0            /usr/lib64/jvm/jre-1.8.0-openjdk/bin/java   1805      auto mode
  1            /usr/lib64/jvm/jre-1.7.0-openjdk/bin/java   1705      manual mode
  2            /usr/lib64/jvm/jre-1.8.0-openjdk/bin/java   1805      manual mode

update-alternatives --config javac
There is only one alternative in link group javac (providing /usr/bin/javac): /usr/lib64/jvm/java-1.8.0-openjdk/bin/javac
Nothing to configure.

update-alternatives --config jar
update-alternatives: error: no alternatives for jar


update-alternatives --config javaws
update-alternatives: error: no alternatives for javaws

update-alternatives --config javaplugin
There are 2 choices for the alternative javaplugin (providing /usr/lib64/browser-plugins/javaplugin.so).

  Selection    Path                                                       Priority   Status
------------------------------------------------------------
* 0            /usr/lib64/java-1_8_0-openjdk-plugin/lib/IcedTeaPlugin.so   18020     auto mode
  1            /usr/lib64/java-1_7_0-openjdk-plugin/lib/IcedTeaPlugin.so   17147     manual mode
  2            /usr/lib64/java-1_8_0-openjdk-plugin/lib/IcedTeaPlugin.so   18020     manual mode

Press enter to keep the current choice
[li], or type selection number[/li]

Should the update-alternatives be install and set for the following things too ?


jexec,appletviewer,apt,extcheck ,idlj,jarsigner ,javadoc, javafxpackager, javah, javap,java-rmi.cgi,jcmd ,jconsole,jcontrol,jdb,jhat,jinfo,jmap,jmc,jps,jrunscript,jsadebugd,jstack,jstat,jstatd,jvisualvm,keytool,native2ascii,orbd,pack200,policytool,rmic,rmid ,rmiregistry,schemagen,serialver,servertool,tnameserv,unpack200,wsgen,wsimport,xjc, java_vm

Will the man pages be available for everything ? or should it be installed ? Should JAVA_HOME User Environment Variable be specified in .bashrc ?

2

Although I haven’t looked at java-1_8_0-openjdk-devel, if it is similar in some ways to previous version implementations…

When you install, the individual JDK-devel binaries should be immediately available. Test by running something like

javac --help

Several others you mention should already work because they are part of the JDK (base openjdk, not the devel package), like java and jar.

I don’t know about any options or implementation for web browser plugin, and I know there are significant architectural differences compared to previous versions of java.

I’ve never thought about using update-alternatives to invoke the “devel” binaries like javac. I don’t know if it makes too much sense unless you have multiple javac (as an example) installed on your system. It makes sense to switch between jre using update-alternatives, though. In its strictest sense, yes the jre is installed as part of the devel package but it’s identical to the standalone jre.

Unless you have both Oracle SE JDK and openjdk-devel installed on the same machine… or multiple versions of openjdk-devel installed (I don’t know if that’d be recommended) I don’t see a use for update-alternatives.

If an update-alternatives solution doesn’t exist for a scenario you need, I’d recommend as alternative solutions running either a Linux container (prob LXC or docker) if you absolutely need performance or virtualization if hardware access isn’t necessary.

TSU

3

well from the config it looks like its been set to the java inside jre. So how do i change java config from jre to the jdk one (all three options are the same)? why do i get error for --config javaws ? update-alternatives: error: no alternatives for javaws .
I am just starting out(newbie) and suggesting Linux container(LXC or docker) might complicate things for me. i havent used them before.

4

I must have explained this incorrectly… Try this…
Think of openjdk-devel(the extras) more like an extension to openjdk(the jre)

Therefor, there should not be any need to switch to openjdk-devel, once installed the “extras” binaries should be immediately available, if not already in a system PATH, then you can create that or use an explicit path in your command.

TSU