> Markdown version of [NetBeans](https://vaadin.com/docs/next/getting-started/dev-environment/run/netbeans). Section index: [llms.txt](https://vaadin.com/docs/next/getting-started/llms.txt)

# Run in NetBeans

You can run and debug your Vaadin application in NetBeans as you would any other Java application. Start by selecting **File** **›** **Project Properties**. Select the **Run** category and specify your **Main Class**, like this:

[Image: NetBeans project properties dialog]

Click **OK** to close the dialog. Next, click the **Debug** button on the toolbar, indicated by a red circle in this screenshot:

[Image: NetBeans debug button]

The application starts up and you can access it at <http://localhost:8080>. Changes to stylesheets are applied to the browser automatically. However, to enable Java hotswap, you have to take some additional actions.

## <a id="enabling-hotswap"></a>Enabling Hotswap

Enabling hotswap manually consists of three steps:

1. Download and install JetBrains Runtime;

2. Download HotswapAgent and install it into JetBrains Runtime; and

3. Update the project configuration so that NetBeans runs the application with JetBrains Runtime and additional JVM parameters.

### <a id="jetbrains-runtime"></a>JetBrains Runtime

You can download the latest version from the [JetBrains GitHub release page](https://github.com/JetBrains/JetBrainsRuntime/releases). Be sure to select the correct architecture. Use JetBrains Runtime to execute your application, not necessarily your IDE.

### <a id="hotswapagent"></a>HotswapAgent

You can download HotswapAgent from the [HotswapAgent GitHub release page](https://github.com/HotswapProjects/HotswapAgent/releases). You’ll need version 1.4.2 or later.

Download the JAR file and place it inside the JetBrains Runtime installation directory as `lib/hotswap/hotswap-agent.jar`. You’ll need to create the `hotswap` folder, and rename the downloaded file to `hotswap-agent.jar`.

If you want to know more about the features of HotswapAgent, the documentation in the [HotswapAgent webpage](https://hotswapagent.org/) is a good resource.

## <a id="project-configuration"></a>Project Configuration

Select **File** **›** **Project Properties**. If the menu item is disabled, your application is likely running and you have to stop it. Then go to the **Build** **›** **Compile** category.

[Image: NetBeans project properties dialog]

Under **JDK Settings**, click **Manage** and locate the JetBrains Runtime. Then select it as your **Java Platform**.

Next, go to the **Run** category. In the **VM Options** field, copy-paste the following:

```
-XX:+AllowEnhancedClassRedefinition -XX:+ClassUnloading -XX:HotswapAgent=fatjar
```

[Image: NetBeans project properties dialog]

Click **OK** to close the dialog, then start the application again. The application starts up.

Open the application in a browser and verify that everything is working through Vaadin Copilot. Move your mouse pointer over the **Copilot** button at the bottom-right corner:

[Image: Vaadin Copilot menu visible in a browser]

> **Important:** The Copilot button is only available when the application is running in development mode. It is not available in production mode.

Now click **Development workflow**. Your browser should look something like this:

[Image: Vaadin Copilot development workflow dialog]

The first item is orange because Vaadin does not have an official plugin for NetBeans. However, Java hotswap is enabled.