Testing if Tomcat is running

[Roman Sokolyuk]

Hi,
Ant: 1.7.1
OS: Mac OS X Leopard
Java: 1.5.0_16
Tomcat: 6

I am using the following ant tasks to stop my Tomcat:

<target name="stop-tomcat">

<exec os="Mac OS X" executable="/bin/sh">

<arg line="${tomcat}/bin/shutdown.sh" />

</exec>

<sleep seconds="5" />

</target>

but when it is executed and Tomcat is already down it obviously throws an
exception.

Could anyone suggest how I could test whether Tomcat is running, and execute
this task only when it is?

Thanks.