spring_reference/IX. ‘How-to’ guides/64.13. Enable Multiple Listeners with Undertow.md

### 64.13. 启用Undertow的多监听器（Multiple Listeners）

往`UndertowEmbeddedServletContainerFactory`添加一个`UndertowBuilderCustomizer`，然后添加一个监听者到`Builder`：
```java
@Bean
public UndertowEmbeddedServletContainerFactory embeddedServletContainerFactory() {
    UndertowEmbeddedServletContainerFactory factory = new UndertowEmbeddedServletContainerFactory();
    factory.addBuilderCustomizers(new UndertowBuilderCustomizer() {

        @Override
        public void customize(Builder builder) {
            builder.addHttpListener(8080, "0.0.0.0");
        }

    });
    return factory;
}
```