A backing bean is a JSF managed bean that contains logic and properties for UI components on a page. Backing beans can act as the state holder of user input and the UI components' data. Backing beans are useful for implementing validation methods and event handler methods that invoke back end application code with component values.

To create a backing bean, you will do the following:

Create a JSF managed bean to hold and process input data
Create an action method in the managed bean
A JSF managed bean is a JavaBean whose instantiation and scope you declaratively set up in the faces-config.xml file. The JavaBean can be any existing class (such as a data transfer class), or it can be a class specific to a page only (hence it is called a backing bean). A backing bean contains the properties that hold the page's data, along with the corresponding accessor methods and/or any other methods (such as navigation or validation) used by the bean. JDeveloper can automatically create a backing bean for a page, or you can elect to create your own backing bean that contains all the properties and logic for the page.
http://www.oracle.com/technetwork/developer-tools/jdev/ccset...

http://docs.spring.io/spring-framework/docs/2.5.6/api/org/sp...