Does Intellij IDEA support debugging a project built with ant?

Question

This project is using Ant as its build system. Can I debug the project when I run it via Ant?

Answer 1

Ant is mainly used for building, not for running Java apps.
But OK, I assume you're running your app using the ant Java task.

Ant Java task

If so, yes, you can do that by using remote debugging.

Remote debugging a Java application

In fact you can debug any Java app like that.
Apps started through ant are still Java apps.

Answer 2

Include this line in your java runtime task, in your build.xml:

<jvmarg value="-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=5005"/>

So for instance if it's ant junit task, it will be like:

<target name="test" depends="test-compile">
    <junit showoutput="yes" fork="true">
        <jvmarg value="-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=5005"/>
    </junit>
</target>

Then run your target

ant clean test

Ant test will wait until we connect a debugger. It will show the output:

test:
    [junit] Listening for transport dt_socket at address: 5005

Then simply create, run a remote run/debug configuration in Intellij (or in your preferred IDE).