KieServices ks = KieServices.Factory.get();
KieFileSystem kfs = ks.newKieFileSystem();
kfs.write("src/main/resources/isA.drl", str);
KieBuilder kbuilder = ks.newKieBuilder(kfs);
kbuilder.buildAll();
assertEquals(0, kbuilder.getResults().getMessages().size());
ks.newKieContainer(kbuilder.getKieModule().getReleaseId()).getKieBase();
KieSession ksession = ks.newKieContainer(kbuilder.getKieModule().getReleaseId()).newKieSession();
assertNotNull( ksession );
List students = new ArrayList();
ksession.setGlobal("students", students);
ksession.insert(new Person("tom", 20));