Force JAVA_HOME during Sun Communications Express configuration

I was with my American bank customer yesterday trying to install and configure a new instance of Sun Messaging Server 7.0 u2.



Simple architecture - single instance, no high-availability, no failover capability. (Ask them why? No budget was the answer. :> )

Anyway, they have this special requirement:

• All components to be installed in a dedicated directory /sjsms
• All components to utilize JDK from a special directory /sjsms/jdk, not the default /usr/jdk in Solaris

Fine, I have no issue. Isn't setting JAVA_HOME=/sjsms/jdk and export the variable into the installation environment will do?

All went fine, except when we tried to configure UWC (Sun Communications Express). Very strange, "configure-uwc" was not able to pick up the JAVA_HOME variable.

A look into the script reveals:

## Look for a Java Runtime Environment#
if [ -x ${INSTALLDIR}/bin/base/jre/bin/java ]; then
  JAVA_HOME=${INSTALLDIR}/bin/base/jre
  export JAVA_HOME
  ## Our private copy of java
elif [ -x /usr/jdk/entsys-j2se/bin/java ]; then
  JAVA_HOME=/usr/jdk/entsys-j2se
  export JAVA_HOME
  ## Standard Orion location
elif [ -x /usr/j2se/bin/java ]; then
  JAVA_HOME=/usr/j2se
  export JAVA_HOME
  ## Standard java location
elif [ ${JAVA_HOME} ]; then
  ## honor JAVA_HOME variable
  :
else
  ## No Java was found. Execute the default java
  ## command to produce a meaningfull L10N message
  ## and then exit.
  /usr/j2se/bin/java
exit 1
fi

Shouldn't the JAVA_HOME variable be consulted first? If it exists, the if-the-else condition should terminate immediately. Weird logic.

Anyway, we change the script to suit the bank's requirement.