Creating dynamic image streaming programmatically

With the graphicImage component, it is possible to render an image that is created programmatically in the server-side backing bean.

How to do it...

The following is an example that renders a PrimeFaces logo that is read with the resource streaming mechanism.

<p:graphicImage value="#{dynaImageController.graphicText}" />

public StreamedContent getGraphicText() throws IOException {
  InputStream stream = this.getClass().getResourceAsStream("/chapter9/primefaces.jpg");
  return new DefaultStreamedContent(stream);
}

How it works…

As seen, the getGraphicText() method returns an instance of StreamedContent. PrimeFaces also provides a default implementation for the stream content, which is org.primefaces.model.DefaultStreamedContent. The backing bean containing the graphicText getter method should be defined in the session scope. The reason behind this is that the image will be fetched in a separate request from the rest of the page content,...