// Check two per-instance mixins were distinct
Lockable lockable1 = (Lockable) tb;
Lockable lockable2 = (Lockable) tb2;
assertFalse(lockable1.locked());
assertFalse(lockable2.locked());
tb.setAge(65);
assertEquals(65, tb.getAge());
lockable1.lock();
assertTrue(lockable1.locked());
// Shouldn't affect second