# Create Domain Model

> Example code is available on [github.com/vaadin-on-grails/gorm-domain](https://github.com/vaadin-on-grails/gorm-domain).

Grails documentation has nice description how to work with [domain](http://grails.org/doc/latest/guide/single.html#domainClasses) classes. In case you are new to Grails domain classes, you should definitelly read it.

Anyway, let's show an example how to create a domain object and use it in Vaadin application.

## Step 1

Run Grails `create-domain` command that will create the new domain class `Item`.

```java
grails create-domain-class com.app.Item
```

The generated and empty domain class `Item.groovy` is in `grails-app/domain/com/app` folder.

## Step 2

Before we start testing the domain class, we need to add there at least one field, for example, a string `label`.

```java
package com.app

class Item {

    String label

    static constraints = {
    }
}
```

> Domain object must be stored in `grails-app/domain`, contain at static field `constraints` to be considered as a valid domain object. Only then a database table for a domain object will be created.

## Step 3

Now, we need to create few records of `Item` in the database during the application start-up.

Open `BootStrap.groovy` and save few `Item` instances there.

```java
import com.app.Item

class BootStrap {

    def init = { servletContext ->
        new Item(label: 'First').save()
        new Item(label: 'Second').save()
        new Item(label: 'Third').save()
        new Item(label: 'Fourth').save()
    }

    def destroy = {
    }
}
```

## Step 4

Use domain class to fetch all records from the database and display them in the browser.

```java
import com.app.Item
import com.vaadin.server.VaadinRequest
import com.vaadin.ui.Label
import com.vaadin.ui.UI
import com.vaadin.ui.VerticalLayout

class MyUI extends UI {

    @Override
    protected void init(VaadinRequest vaadinRequest) {

        VerticalLayout layout = new VerticalLayout()
        layout.setMargin(true)

        List<Item> items = Item.findAll()
        for (Item item : items) {
            String label = item.label
            layout.addComponent(new Label(label))
        }

        setContent(layout)
    }
}
```

Run the application and database records will be displayed in UI.

![Records from database displayed in browser](http://vaadinongrails.com/book/2_1_1_domains_in_browser.png)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://ondrej-kvasnovsky-2.gitbook.io/vaadin-on-grails/database/gorm/create_model.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.