Other technical questions

Is Orbeon Forms an XForms Engine?

Orbeon Forms includes an XForms engine (also known as an XForms processor), which we refer to as the Orbeon Forms XForms engine.

But Orbeon Forms also includes:

  • the Form Builder authoring tool

  • the Form Runner runtime

  • an XML pipeline engine running the XPL pipeline language

  • an application controller (the Page Flow Controller or PFC)

You are free to use Orbeon Forms for its XForms functionality only, but you can also leverage more of Orbeon Forms to build your forms-based application.

What differentiates Orbeon Forms from other web solutions?

A few things come to mind:

  1. Orbeon Forms is not intended to be a general-purpose web app platform, but instead focuses on forms, typically large forms, and handling many of them. It's not uncommon for users to have hundreds of forms to create and deploy, or to have forms with hundreds of fields (sometimes more than 1000 fields).

  2. Although from time to time customization is required, and some complex rules do require the use of XPath, Orbeon Forms strives not to require coding in Java, JavaScript or other programming languages. Instead, Orbeon Forms provides an authoring tool and a runtime environment that try to do as much as possible out of the box.

  3. Orbeon Forms does not rely on any particular proprietary technology, unlike solutions from some large companies.

How can I remove the sample applications from my Orbeon Forms deployment?

See Creating a Production WAR.

How can I remove Form Runner / Form Builder from my Orbeon Forms deployment?

Under the WAR file's WEB-INF/lib directory, remove:

  • if you are not using Form Builder: orbeon-form-builder.jar

  • if you are using neither Form Builder nor Form Runner: orbeon-form-runner.jar

NOTE: Form Builder also requires orbeon-form-runner.jar.

See also Creating a Production WAR.

How can I know which version of Orbeon Forms I am running?

The full version number is logged on the server when the Orbeon Forms web application starts.

You can set the following property in your properties-local.xml:


This is done automatically if you run Orbeon Forms in dev mode.

You will see the version number appear at the bottom of Orbeon Forms pages.

I am getting frequent Out of Memory errors with Orbeon Forms. What can I do?

The first thing to check is whether your Java VM has enough heap memory as documented in Installation.

What should I make of the SocketException I see in the logs?

In most cases, this exception doesn't reflect any problem. Browsers make requests to Orbeon Forms, which answers by sending data back to the browsers. Requests can be for web pages (e.g. forms), CSS files, images, and more. You will get this exception if, while Orbeon Forms sends data back to the browser, the connection between the browser and the server is interrupted.

In most cases, this happens because the browser cut the connection, as a way to tell the server don't bother, after all, I don't need this. This can happen if users clicked on a link to load a page, and while the page is being loaded interrupt the browser, for instance by clicking on another link (assuming the previous page is still visible), or pressing the escape key or the equivalent browser button, or closing the browser window or tab. Unless you also see another user-facing issue, you don't need to worry about this exception in the logs.