When developing OSGi Plugins, you should have your own development server running on your local machine. Not only because of the faster deployment of changes (a new version of a plugin must always deployed with a HTTP restart), but because of the Java debugging posibilities: Only one Eclipse instance can connect to the JVM, and every request processed by the server will start the debugger. If multiple users a accessing the server while you are debugging, your Eclipse will try to debug every incoming request, and this can lead into a confusing situation for all.
To enable debugging, you first have to add two parameters to the notes.ini:
JavaEnableDebug=1
JavaDebugOptions=transport=dt_socket,server=y,suspend=n,address=8000This starts the debugging on port 8000. Feel free to change the value to every port you want. Because of security reasons you should not start debugging on a productive machine.
After restarting the domino server, you can connect to the JVM in your Eclipse IDE by creating a new JVM remote debugging session. Create a new debug configuration…
… choose (1) „Remote Java Application„, (2) give a name to it, (3) select the plugin project, (4) enter the port the server listens, and click on (5) „Apply„.
If you want to connect to your server, you need to start debugging by clicking on the project:
After setting a breakpoint and sending a request to the servlet, Eclipse switches to the Debug perspective where you can look what happens with your servlet.
Sometimes you are connecting to the „wrong“ JVM, because a Java agent is running and/or a DOTS task does it’s job. It’s better to disable these tasks on your development server.
During debugging you are able to hotswap your code, but keep in mind that after a restart of the HTTP JVM all your changes are no longer „installed“. You have to build a new plugin or replace your code during runtime again.
In the next blog post, let’s talk about our development tools.
