LINUX-How can I start/stop tomcat server in Linux machine?

1) First download the Linux tomcat version.
2) Unzip it.
3) Go to the tomcat bin folder.
4) Run the startup.sh for start the tomcat server
5) Shutdown.sh for using to stop the tomcat

START TOMCAT :

$/opt/user/>export JAVA_HOME=/usr/local/j2sdk1.6
$/opt/user/>export CATALINA_OPTS="-Djava.awt.headless=true"
$/opt/user/>export JDK_HOME=${JAVA_HOME}
$/opt/user/>export CATALINA_HOME=/usr/local/tomcat6
$/opt/user/>${CATALINA_HOME}/bin/startup.sh

STOP TOMCAT :

$/opt/user/>export JAVA_HOME=/usr/local/j2sdk1.6
$/opt/user/>export CATALINA_OPTS="-Djava.awt.headless=true"
$/opt/user/>export JDK_HOME=${JAVA_HOME}
$/opt/user/>export CATALINA_HOME=/usr/local/tomcat6
$/opt/user/>${CATALINA_HOME}/bin/shutdown.sh