### Question:
TreeList { public void populate(final List<TreeListItem> items) { currentItems = items; refresh(); } @Inject  TreeList(final View view); void populate(final List<TreeListItem> items); void refresh(); List<TreeListItem> getCurrentItems(); void clear(); Node getElement(); void clearSelection(); List<TreeListItem> getSelectedItems(); void setOnSelectionChanged(final Consumer<List<TreeListItem>> onSelectionChanged);  }### Answer:
@Test public void testPopulate() { doNothing().when(treeList).refresh(); final List items = mock(List.class); treeList.populate(items); verify(treeList).refresh(); }