protected void build(C instance) {
        if (!StringUtils.isEmpty(id)) {
            instance.setId(id);
        }
    }
@Test
    void build() {
        Builder builder = new Builder();
        builder.id("id");

        Config config = builder.build();
        Config config2 = builder.build();

        Assertions.assertEquals("id", config.getId());

        Assertions.assertNotSame(config, config2);
    }