#94 Make output verification of pmd more strict

[Andreas Sewe]

Currently (DaCapo 9.12), the harness verifies the pmd benchmark's stderr.log output only (it has to be empty). I have, however, observed some differences in the stdout.log output from JVM to JVM.

Jikes RVM 3.1.2:
org.apache.tools.ant.Task not found in org.dacapo.harness.DacapoClassLoader{url....
HotSpot 20.1-b02:
Could not find class net.sourceforge.pmd.ant.PMDTask, due to: java.lang.NoClassDefFoundError: org/apache/tools/ant/Task

These differences in output make me doubt that the two JVMs indeed are subjected to the same workload (also, because Jikes RVM is significantly faster on this benchmark then HotSpot, which is rather unusual). This is just a hunch, though.

At any rate, pmd currently sports a rather loose output verification (empty stderr.log), so making this more strict is probably a good idea.