### Question:
ContainerAdapter implements GriffonPivotAdapter, org.apache.pivot.wtk.ContainerListener { public void focusTraversalPolicyChanged(org.apache.pivot.wtk.Container arg0, org.apache.pivot.wtk.FocusTraversalPolicy arg1) { if (focusTraversalPolicyChanged != null) { focusTraversalPolicyChanged.call(arg0, arg1); } }  CallableWithArgs<Void> getComponentInserted(); CallableWithArgs<Void> getComponentsRemoved(); CallableWithArgs<Void> getFocusTraversalPolicyChanged(); CallableWithArgs<Void> getComponentMoved(); void setComponentInserted(CallableWithArgs<Void> componentInserted); void setComponentsRemoved(CallableWithArgs<Void> componentsRemoved); void setFocusTraversalPolicyChanged(CallableWithArgs<Void> focusTraversalPolicyChanged); void setComponentMoved(CallableWithArgs<Void> componentMoved); void componentInserted(org.apache.pivot.wtk.Container arg0, int arg1); void componentsRemoved(org.apache.pivot.wtk.Container arg0, int arg1, org.apache.pivot.collections.Sequence<Component> arg2); void focusTraversalPolicyChanged(org.apache.pivot.wtk.Container arg0, org.apache.pivot.wtk.FocusTraversalPolicy arg1); void componentMoved(org.apache.pivot.wtk.Container arg0, int arg1, int arg2);  }### Answer:
@Test public void testFocusTraversalPolicyChanged() { final boolean[] invoked = new boolean[1]; CallableWithArgs<Void> callable = new CallableWithArgs<Void>() { public Void call(Object... args) { invoked[0] = true; return null; } }; assertNull(adapter.getFocusTraversalPolicyChanged()); adapter.focusTraversalPolicyChanged(null, null); assertFalse(invoked[0]); adapter.setFocusTraversalPolicyChanged(callable); adapter.focusTraversalPolicyChanged(null, null); assertTrue(invoked[0]); }