Preview:
http://picasaweb.google.com/PaksyDavid/Screenshots/photo#5218735607356936946

It might be interesting to write a quick performance program to see if there is any impact for something simple like mathematical evaluations.

#!/bin/sh
done=0
while [ “$done” -eq 0 ]
do
java &
jvmPID=$!
trap “kill -TERM $jvmPID;done=1″ TERM
wait $jvmPID
echo “respawning JVM”
done
kill -TERM $jvmPID
echo “Out of the loop!!”

Note, we will need to change “kill -9 $javaServerPID” to “kill -TERM $javaServerPID” in the previous script.
I hope that helps.
Java Jiggler

This can be acomplished by launching the rmi registry and the java server(s) in one script.

1. The idea is that the rmi sever will be launched first.
2. The java rmi server will be launched next.
3. The launch script will than block using a wait command to check if rmi registry terminates.
4. If wait unblocks, that means that rmi registry terminated. When this happens, kill the java server(s) and repeat steps 1-3.

Below is a sample script. You can tested it by killing the rmi registry and see it respawn both rmi registry and a java server.

Here is a sample: (Note: this should work but has not been tested for syntax)

#!/bin/sh

#kick off the rmi registry
./rmiRegistry &

#store the PID of the RMI registry
rmiRegistryPID=$!
echo Started RMI registry with PID= $rmiRegistryPID”

#kick off the java server in a script
./startJavaServer &

#store PID for java server
javaServerPID=$!
echo Started Java server with PID= $javaServerPID”

While [ 1 ]
do
wait $rmiRegistryPID
echo “RMI Registry (PID=$rmiRegistryPID ) terminated…”

kill -9 $javaServerPID
echo “Terminated Java Server”

./rmiRegistry &
rmiRegistryPID=$!
echo “Respawned RMI registry with PID= $rmiRegistryPID”

./startJavaServer &
javaServerPID=$!
echo “Respawned Java server with PID= $javaServerPID”
done