ModelHelper.modelAdd(model, "a P b; w R x");
ModelHelper.modelAdd(model2, "w R x; y S z");
final Model um = model.union(model2);
Assert.assertFalse(model.containsAll(model2));
Assert.assertFalse(model2.containsAll(model));
Assert.assertTrue(um.containsAll(model));
Assert.assertTrue(um.containsAll(model2));
for (final StmtIterator it = um.listStatements(); it.hasNext();)
{
final Statement s = it.nextStatement();
Assert.assertTrue(model.contains(s) || model2.contains(s));