OutputStream os = new FileOutputStream(new File(getTestCaseDir(), "config-default.xml"));
XConfiguration defaultConf = new XConfiguration();
defaultConf.set("a", "AA");
defaultConf.set("b", "BB");
defaultConf.set("e", "${d}${d}");
defaultConf.writeXml(os);
os.close();
final DagEngine engine = new DagEngine(getTestUser());
Configuration conf = new XConfiguration();
conf.set(OozieClient.APP_PATH, workflowPath);