@Test
    void invalidMaxConnectionAge() {
        assertThatThrownBy(() -> Server.builder().maxConnectionAgeMillis(-1))
                .isInstanceOf(IllegalArgumentException.class)
                .hasMessageContaining("expected: >= 1000 or == 0");

        assertThatThrownBy(() -> Server.builder().maxConnectionAgeMillis(100))
                .isInstanceOf(IllegalArgumentException.class)
                .hasMessageContaining("expected: >= 1000 or == 0");
    }
Makes sure that {@link ServerBuilder#decorator(DecoratingHttpServiceFunction)} works at every service and
virtual hosts and {@link VirtualHostBuilder#decorator(DecoratingHttpServiceFunction)} works only at
its own services.
core/src/test/java/com/linecorp/armeria/server/ServerBuilderTest.java