How should I know which JAVA

[Former Member]

Hello

How should I know which JAVA I have installed on: when Issue-ing command "java -version".

I get response like :

java version "1.4.2"

Java(TM) 2 Runtime Environment, Standard Edition (build 2.3)

IBM J9 VM (build 2.3, J2RE 1.4.2 IBM J9 2.3 Linux amd64-64 j9vmxa64142-20080923 (JIT enabled)

J9VM - 20080922_23329_LHdSMr

JIT - 20080815_1845_r8

GC - 200809_04)

I know it comes from files like "IBMJava2-AMD64-142-SDK-1.4.2-12.0.x86_64.rpm" or " IBMJava2-AMD64-142-SDK-1.4.2-13.2.x86_64.rpm"

But how to find out. It is an productive system so I can not "try"

Thank you in advance

[Former Member]

solved

[Former Member]

Hello

In any case java is instaled to /opt/IBMJava2-amd64-142 (this is an unix machine). This is also JAVA_HOME and SAPINST.... variable

This is when I install from "IBMJava2-AMD64-142-SDK-1.4.2-12.0.x86_64.rpm" or from "IBMJava2-AMD64-142-SDK-1.4.2-13.2.x86_64.rpm". When I enter java -version I get (as stated before):

java version "1.4.2"

Java(TM) 2 Runtime Environment, Standard Edition (build 2.3)

IBM J9 VM (build 2.3, J2RE 1.4.2 IBM J9 2.3 Linux amd64-64 j9vmxa64142ifx-20090909 (JIT enabled)

J9VM - 20090908_41946_LHdSMr

JIT - 20090210_1447ifx1_r8

GC - 200902_24)

How could I know it comes from "IBMJava2-AMD64-142-SDK-1.4.2-13.2.x86_64.rpm"(version 13 i.e latest) or "IBMJava2-AMD64-142-SDK-1.4.2-12.0.x86_64.rpm"

Kindly please for help

[former_member185954]

Hello Jo,

There maybe different versions of java installed on your server depending on the Server build (Non SAP Apps).You could locate the java your SAP is using by logging into the server as <sid>adm and executing the command.

which java

This should give you the filepath of the java being invoked. Further try to execute that path with the following options:

-fullversion

-showversion

I think -fullversion should be able to give you the required output that you seek.

Regards,

Siddhesh

[nelis]

How could I know it comes from "IBMJava2-AMD64-142-SDK-1.4.2-13.2.x86_64.rpm"(version 13 i.e latest) or "IBMJava2-AMD64-142-SDK-1.4.2-12.0.x86_64.rpm"

After you have run: rpm -qa |grep -i java ...run: rpm -q --filesbypkg <java package>

It will list where the files are installed for that package. Then based on the location of 'echo $JAVA_HOME' you will know which package it is using.

Nelis

[ErvinSzolke]

Hi Jan,

if the question is: how to determine (and change) the JDK of the J2EE Engine, then see the note:

#718901 How to Change the JDK of the J2EE Engine

(http://service.sap.com/sap/support/notes/718901)

Here the JAVA_HOME does not count at all, only the jstartup/vm/home parameter.

If the question is: which JDK will be displayed if I have many JDKs on my system and I execute "java -version" then the answer is that it depends on the PATH variable. The first JDK which will be found in your $PATH environment variable will be displayed this case.

I hope this helps.

Best Regards,

Ervin

[Former Member]

You can also check the environmental variables to see which JAVA has been exported.

On the command line use: env (env | grep JAVA_HOME / SAPINST_JRE_HOME)

Also the IBM Java is installed under /opt/IBM-142* on linux

Matsobane Masibe

SAP Netweaver Administrator

[nelis]

But how to find out. It is an productive system so I can not "try"

What do you mean you cannot try ? There is no harm done in checking the version.

If you have a Java AS running you can connect to http://hostname:5<sys-num>00/monitoring/SystemInfo where you can also check the Java version being used.

If it's installed using a rpm package you can check what's installed with the following command: rpm -qa |grep -i java

Nelis