dataStoreParams.put("intKey", 999);
        assertEquals("999", dataStoreParams.getAsString("intKey", "defaultValue"));
    }

    // Test containsKey
    public void test_containsKey() {
        assertFalse(dataStoreParams.containsKey("key1"));

        dataStoreParams.put("key1", "value1");
        assertTrue(dataStoreParams.containsKey("key1"));

        dataStoreParams.put("key2", null);