@Test
public void testDiffWindow() {

    CEPWindow window1 = new CEPWindow();
    window1.setOperator("dummyOp1");
    column1.setWindow(window1);
    CEPWindow window2 = new CEPWindow();
    window2.setOperator("dummyOp2");
    column2.setWindow(window2);
    checkSingleDiff(FIELD_WINDOW, window1, window2, column1, column2);
    assertNotEquals(column1, column2);
}