If I run rhamt-cli with no --output parameter, I have:

wadez-wood:servers Akram$ rhamt-cli --input lab-1/simple-sample-app.ear --packages com.acme --output
Using RHAMT at /Users/Akram/servers/bin/rhamt-cli-4.0.0-SNAPSHOT
> Red Hat Application Migration Toolkit (RHAMT) CLI, version 4.0.0-SNAPSHOT.
RHAMT execution failed due to: Index: 5, Size: 5
java.lang.IndexOutOfBoundsException: Index: 5, Size: 5
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.get(ArrayList.java:429)
at org.jboss.windup.bootstrap.commands.windup.RunWindupCommand.runWindup(RunWindupCommand.java:154)
at org.jboss.windup.bootstrap.commands.windup.RunWindupCommand.execute(RunWindupCommand.java:73)
at org.jboss.windup.bootstrap.Bootstrap.executePhase(Bootstrap.java:454)
at org.jboss.windup.bootstrap.Bootstrap.run(Bootstrap.java:319)
at org.jboss.windup.bootstrap.Bootstrap.main(Bootstrap.java:101)

https://github.com/windup/windup-distribution/issues/47