// Test with null output
        String[] inputs = { "input" };
        CharMappingItem item = new CharMappingItem(1L, inputs, null);

        assertNull(item.getOutput());
    }

    public void test_constructor_withUnsortedInputs() {
        // Test that inputs are sorted during construction
        String[] inputs = { "z", "a", "m" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "output");