What is difference between JRE and JDK in Oracle 9i

[Frank de Vries]

Hi,
I am installing a second Oracle 9i on
the same node. It is a hpux11.00 with Mc/Serviceguard and we need an Oracle installation per package.
There are 2 packages and 2 nodes (Thus 4 in total)

I also have existing Oracle8i installation.
They will be superseeded.

But during the installation of 9i I need to give a path for JDK_HOME.

And I am doubtfull to what path to give.
I did a search for "*jre*" and I got so many
responses:

/opt/java1.3/jre
/usr/oracle/product/9.2.07/jdk/jre
/usr/local/java1.3/jre
/var/spool/sw/Jre13/JRE13-COM/opt/java1.3/jre

Do I just organise this myself, then what is
the best practise for the JDK_HOME path ?
$ORACLE_HOME/jdk ??

Your suggestions and comments are welcome.

[Steven E. Protter · Accepted solution]

Shalom,

JRE is the run time package for Java.

JDK is the development kit.

The best practice with this stuff is to keep it in the /opt/java/java1.x directory and not keep it anywhere near any oracle binaries.

Note that the bell tolls for HP-UX 11.00 at the end of this calendar year. Time to plan that upgrade.

SEP

[Robert-Jan Goossens]

Hi,

Install the dev kit.

http://www.hp.com/products1/unix/java/

Regards,
Robert-Jan

[rariasn]

Hi Frank,


Use the JAVA than include ORACLE 9.2 software

Verify prerequisites for JAVA and kernel parameters.

rgs,

ran

[rariasn]

Hi Frank,


Use the JAVA that include ORACLE 9.2 software

Verify prerequisites for JAVA and kernel parameters.

rgs,

ran

[Matti_Kurkela]

JDK refers to Java Development Kit, which contains the JRE + development tools. There can be several JDKs installed on one host.

Probably the full version numbers are slightly different in each: check the full version numbers (you would generally prefer 1.3.1.xx over 1.3.0.xx) with e.g. "/opt/java1.3/bin/java -version" command. Then use the one that best fits your requirements (generally the latest is better, unless you specifically need an older version).

A bit of explanation about your search results:

- /opt/java1.3/jre = the standard location for HP-supplied Java 1.3 series .depot package. This may be a "full" JDK, or a smaller JRE-only package with no Java development tools. In this case, the JDK_HOME value would be "/opt/java1.3". This is the easiest to update to another HP-supported Java package.

- /usr/oracle/product/9.2.07/jdk/jre = Java Development Kit provided by Oracle installation. If you intend to use this JDK, the JDK_HOME value would probably be "/usr/oracle/product/9.2.07/jdk".

- /usr/local/java1.3/jre = Java installed in a custom path, possibly because a specific version was needed. Suitable JDK_HOME value to use this one is probably "/usr/local/java1.3".

- /var/spool/sw/... = This is not a Java installation, but a data file for swagentd to record the fact that a Java package is installed in /opt/java1.3/jre on this host. Don't touch this one manually; it is needed by swinstall and other sw* tools and will be removed automatically when no longer needed.

[Frank de Vries]

okay, that explains a lot.

I think I go with Steven's advice
So if I already have /opt/java/1.3

I just re-use it ?

It appears I cannot skip the java JDK installation with the Oracle installer
if I already have it on /opt/java/1.3

Or will the Oracle installer be smart and
see I already have it and skip itself.


In any case what I understand from our developers , that all Java development is
not done on unix but on Windows (Tools Like Java WebSphere studio) and then ported to unix when it is ready. So I do not really
need it on unix anyway.