Question

I have a java program that stops often due to errors which is logged in a .log file. What can be a simple shell script to detect a particular text in the last/latest line say

[INFO] Stream closed

and then run the following command

java -jar xyz.jar

This should keep on happening forever(possibly after every two minutes or so) because xyz.jar writes the log file.

The text stream closed can arrive a lot of times in the log file. I just want it to take an action when it comes in the last line.

Answer 1

How about

while [[ true ]];
do
  sleep 120
  tail -1 logfile | grep -q "[INFO] Stream Closed"
  if [[ $? -eq 1 ]]
  then
    java -jar xyz.jar &
  fi
done