linux automatically restart tomcat script

#!/bin/sh  
pid = `ps aux | grep tomcat | grep -v grep | grep -v retomcat | awk '{print $ 2}' `  
echo $pid  
if [ -n "$pid" ]  
then  
{  
        echo =====kill tomcat ==========  
        kill -9 $pid  
        sleep 3  
        echo =========startup.sh =============  
        /usr/local/tomcat/bin/startup.sh  
}  
else  
echo ===========startup.sh=============  
/usr/local/tomcat/bin/startup.sh  
  
be