Structure Nodes and Structure Binding 

When defining context nodes you can use structures that were defined previously in the Java Dictionary. This is referred to as structure binding a context node.

These types of context nodes contain at runtime all of the fields defined in the Dictionary structure as context attributes with the same name. If the Dictionary data is read for example by an ABAP system at runtime, then a context node also contains those context attributes that were not added to the Dictionary structure until later (after the structure binding was defined at design time).

Only simple data types are currently supported for structure binding between context nodes and the Java Dictionary. Furthermore, it is not possible to add additional context attributes in a context mode that is bound to a structure. This is because such additional attributes may conflict at runtime with those fields that were not defined in the structure until later. If context attributes are deleted from a node that is bound to a Dictionary structure, then this only results in access methods not being generated in the context interface. At runtime, these attributes are still available in the node elements and can be accessed using generic context interfaces (such as IWDNode and IWDNodeElement).

However, it is possible that child nodes of type non-singleton can be added to such context nodes that are bound to a Dictionary structure. For child nodes of type non-singleton, a separate instance of the child node in which (or rather – in whose context attributes) element-specific data can be saved exists at runtime in each node element of the parent node. Node cardinality 1..1 is recommended for this type of non-singleton child nodes.