Re: Can I detect Java version before my java program starts?

[Bruce Jin <brucej@xxxxxxxxxxxxxxxxxxxx>]

You can try these two methods:

1. In CL check the folder existence to decide if a particular JDK 
version is installed. E.g. /QIBM/ProdData/Java400/jdk14 is the location 
of JDK 1.4.
2. If you call qshell scripts in CL you can check installed JDK using 
something like this:
jdk14=/QIBM/ProdData/Java400/jdk14
jdk13=/QIBM/ProdData/Java400/jdk13
jdk12=/QIBM/ProdData/Java400/jdk12
if cd $jdk14
  then jv=4
elif cd $jdk13
  then jv=3
elif cd $jdk12
  then jv=2
else
  echo Connot find $jdk12 or $jdk13 or $jdk14!
fi
jdk=/QIBM/ProdData/Java400/jdk1$jv
echo Found JDK 1.$jv, use $jdk.
export -s JAVA_HOME=$jdk

I hope someone has better ways to do this.

Bruce

TitanRebel wrote:

> I am starting a Java application on the iSeries.  I don't really care 
> which version of Java the iSeries is using as default (as long as it's 
> above 1.3.1).  The problem is that in the CL program that uses the 
> JAVA command to start he application, I have to "hard code" the 
> classpath to include a reference to the tools.jar file found in the 
> JAVA_HOME directory.  As you know this path changes based on the 
> version of Java being used.
>
> Is there a way that I can detect the version of java prior to program 
> start and add the appropriate classpath entry then?  Right now, a CL 
> is starting the Java program "directly" with the JAVA command.  This 
> could be changed to use a QSHELL script, but I still don't know how I 
> would do this in a shell script either.
>
> Any help would be appreciated.
>
> Thanks,
>
> Ken