### Question:
SpaceAdaptor extends QBeanSupport implements SpaceAdaptorMBean { public Set getKeys () { if (sp instanceof LocalSpace) return ((LocalSpace)sp).getKeySet (); return null; } SpaceAdaptor(); synchronized void setSpaceName(String spaceName); String getSpaceName(); Set getKeys();  }### Answer:
@SuppressWarnings("unchecked") @Test public void testGetKeys() throws Throwable { Set result = new SpaceAdaptor().getKeys(); assertNull(result, "result"); }