Update PrimeFaces dataTable from backing bean

Assuming you'll be calling a Java method using Listener from Fingerprint device API, and from ManagedBean you can update any Primefaces Component using RequestContext.

RequestContext.getCurrentInstance().update("ID_OF_YOUR_DATATABLE")

There's already a component in Primefaces, as you can see : here.

RequestContext is a feature with various handy utilities.

Update component(s) programmatically. Execute javascript from beans. Add ajax callback parameters. ScrollTo a specific component after ajax update.

Have a look here for an example.