// Test equality
        assertTrue(data1.equals(data2));
        assertTrue(data2.equals(data1));
        assertEquals(data1.hashCode(), data2.hashCode());

        // Test reflexivity
        assertTrue(data1.equals(data1));

        // Test with null
        assertFalse(data1.equals(null));

        // Test with different class
        assertFalse(data1.equals("string"));
    }