1) Start tomcat with this command
~/apache-tomcat-7.0.47/bin/catalina.sh jpda start -Xdebug -Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=n
OR
2) export CATALINA_OPTS='-Djava.awt.headless=true -Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8000'
And attache IDE to 8000 remote process.