How do I start hacking Tomcat in Eclipse?
$ git clone https://github.com/apache/tomcat.git (or whatever branch you want: clearly, this would be better to do directly from within Eclipse but it's easier to describe as a command) $ cd tomcat $ echo "base.path=/path/to/where/tomcat/can/put/its/3rd-party/libs" > build.properties $ ant ide-eclipse
Then, in Eclipse, go to Preferences | Java/Build Path/Classpath Variables and set the following variables:
ANT_HOME=path to your Ant install (where lib/ant.jar can be found) TOMCAT_LIBS_BASE=[whatever you set base.path to above]
The port does not need to be set to 8000, it may be any value appropriate for your system.
If you need to debug Tomcat startup or the auto-deployment of an application (where a breakpoint set in a debugger would be reached before you have time to connect with the debugger), then set the parameter
suspend=y instead of
suspend=n. Doing this will cause the JVM to pause execution very early in the launch process and wait until a debugger is attached before proceeding.
Whilst this is very useful in development it should not be used in production because of both security and performance implications.