TaskStub task1 = new TaskStub("0", "dan.encryption.Digest.md5");
task1.setInput("message", "dude");
tasks.add(task1);
TaskStub task2 = new TaskStub("1", "dan.encryption.Digest.md5");
task2.setInput("message", new TaskStubOutputReference(task1, "digest"));
tasks.add(task2);
submission.setInput("inputTasks", tasks);