> Markdown version of [Vaadin On Grails Multiple UIs](https://vaadin.com/docs/v8/framework/articles/VaadinOnGrailsMultipleUIs). Section index: [llms.txt](https://vaadin.com/docs/v8/framework/llms.txt)

# <a id="vaadin-on-grails-multiple-uis"></a>Vaadin on grails - multiple UIs

*Versions used in this tutorial: Grails 2.3.x, Vaadin 7.1.x. News and updates about Vaadin on Grails are available on [VaadinOnGrails](https://twitter.com/VaadinOnGrails). This is continuation of [Vaadin on Grails - Database access](https://vaadin.com/docs/v8/framework/articles/VaadinOnGrailsDatabaseAccess.md)*

In `grails-app/conf/VaadinConfig.groovy`, we can change URL mapping to UI. Also, we can define multiple UIs to be accessible from one Grails application.

Create two new UIs that we will show under different URLs. `ClientUI` will be available on <http://localhost:8080/client> and `ServerUI` on <http://localhost:8080/server>

```java
class ClientUI extends UI {
  protected void init(VaadinRequest request) {
    VerticalLayout layout = new VerticalLayout()
    layout.setMargin(true)
    Label label = new Label("Client")
    layout.addComponent(label)
    setContent(layout)
  }
}

class ServerUI extends UI {
  protected void init(VaadinRequest request) {
    VerticalLayout layout = new VerticalLayout()
    layout.setMargin(true)
    Label label = new Label("Server")
    layout.addComponent(label) setContent(layout)
  }
}
```

Open `VaadinConfig.groovy` and change the mapping, so the mapping points to the new UIs.

```
mapping =
[ "/client/*": "app.ClientUI",
  "/server/*": "app.ServerUI"]
```

Now we can start up the application and access both URLs to see each is mapped to different UI class.

[Image: Mapping UIs]