Could not find property 'classesDir' on source set main

Hello.

When building the tasks-javaexec-task example from

https://github.com/gradleware/oreilly-gradle-book-examples

I get a:

groovy.lang.MissingPropertyException: Could not find property ‘classesDir’ on source set main.

This has been tried on 1.0-milestone-9 (on milestone 3 it stops even earlier due to some dependency failure).

I could not find any reference around related to this problem. It seems like an error in the script, but it would be quite strange indeed, given the “pseudo-official” nature of the source.

‘SourceSet.classesDir’ has been deprecated for a while. Versions before m9 should print a message that the correct replacement is ‘SourceSet.output.classesDir’. The [migration guide] (http://wiki.gradle.org/display/GRADLE/Gradle+1.0-milestone-9+Migration+Guide) for m9 mentions that ‘SourceSet.classesDir’ has finally been removed.

“Versions before m9 should print a message that the correct replacement is SourceSet.output.classesDir.”

You might want to put that back in since there are countably infinite examples which still refer to SourceSet.classesDir in one way or another.

You could probably use

sourceSets.main.output.classesDir

instead. Works for test.