ManagedBean vs BackingBean

ManagedBean - A managed bean is simply a java bean that is registered in faces-config file.

• Holds presentation and business logic
• Store state for example information about authenticated user
• Execute a java routine
• Define handler for event listners

Backing Beans

• Contain getter and setter methods for UI components
• Have one to one relationship with a page

 http://sqltech.cl/doc/oas10gR31/web.1013/b28967/web_getstarted005.htm
http://docs.oracle.com/cd/E15523_01/web.1111/b31973/gs_jdev.htm#ADFUI824

Data Control  - a meta data interface for business service

• They abstacts the implementation specific details of underlying business service. Regardless of business service based on database, webservice or pojo objects, data control exposes that business service in exact consistent way
• Uses standard meta data interface to describe services' operations and collections
• At design time, simplifies binding components to data control operation or data collection.
• At run time, wires business service data controls to UI bindings from XML files
• Built in data controls
• ADF BC
• java class
• ejb
• url(xml or csv)
• web service
• place holder

Data Bindings:

• They provide particular way to bind your business service to UI items. 
• They abstract the details of accessing data from the data collections and of invoking its operations
• Three kinds of declarative bindings
• Iterator binding - tracks current row in a data collection
• value binding - Binds UI components to attribute values in a data collection
• action binding - To invoke operations
• Types of binds
• Attribute binding - Input text item to a String value
• Tree binding - Table or tree to a data collection
• List binding - Exports list of legal values, enabling the user to select one
• Action binding - Builtin operation or custom method

Executables:  Link bindings to data controls. It just acts as current record indicator that ensures the binding is pointing to correct record within rowset. 

• Iterator
• Method iterator
• Access iterator
• Variable iterator

ADF control and ADF databindings work together to provide very simple way of binding data services to ui components

Bindings Metadata Summary:

• Page def.xml 
• Page def file at design time becomes the binding container at runtime
• DataBindings.cpx  //Created when data control is dragged and dropped on UI
• It gives a binding context, that contains Binding Container and Data control
• Provides meta data from which Oracle ADF bindings objects are created at run time
• It contains Page Map, page def file & Data Control usages
• datacontrol desc.dcx  // for Non ADFBC components
• Structure def.xml  // for Non ADFBC components

ADF binding in the ADF Faces UI
Every component on page is bound to binding file/pagedef file/binding container. At design time the bindings are represented as meta data. At run time they are represented as java object that can be accessed by managed bean.

Commonly used binding object:

• BindingContainer or DCBindingContainer
• DCIteratorBinding
• AttributeBinding
• JUCtrlHierBinding,  JUCtrlHierNodeBinding
• JUCtrlListBinding
• OperationBinding

How to access the ADF binding layer from managed bean using Java?