@Test
public void testSetFilter() {

    final ImportOptions delegate = new ImportOptions();
    final InternalImportOptions options = new InternalImportOptions(pid, delegate, null);
    final WorkspaceFilter listener1 = mock(WorkspaceFilter.class);
    final WorkspaceFilter listener2 = mock(WorkspaceFilter.class);
    delegate.setFilter(listener1);
    assertSame("instance1", listener1, options.getFilter());
    delegate.setFilter(listener2);
    assertSame("instance2", listener2, options.getFilter());
    options.setFilter(listener1);
    assertSame("instance1", listener1, delegate.getFilter());
    options.setFilter(listener2);
    assertSame("instance2", listener2, delegate.getFilter());
}