Header manipulation and propagation is a key business integration messaging requirement. Components such as Oracle BPEL Process Manager, Oracle Mediator, Oracle JCA adapters, REST adapters, and Oracle B2B rely extensively on header support to solve customers' integration needs. For example, you can preserve a file name from the source directory to the target directory by propagating it through message headers. In Oracle BPEL Process Manager and Oracle Mediator, you can access, manipulate, and set headers with varying degrees of user interface support.

A normalized message is simplified to have only two parts, properties and payload.

Typically, properties are name-value pairs of scalar types. To fit the existing complex headers into properties, properties are flattened into scalar types.

The user experience is simplified while manipulating headers in design time, because the complex properties are predetermined. In the Mediator Editor or Oracle BPEL Designer, you can manipulate the headers with some reserved key words.

However, this method does not address the properties that are dynamically generated based on your input. Based on your choice, the header definitions are defined. These definitions are not predetermined and therefore cannot be accounted for in the list of predetermined property definitions. You cannot design header manipulation of the dynamic properties before they are defined. To address this limitation, you must generate all the necessary services (composite entry points) and references. This restriction applies to services that are expected to generate dynamic properties. Once dynamic properties are generated, they must be stored for each composite. Only then can you manipulate the dynamic properties in the Mediator Editor or Oracle BPEL Designer.

For information about normalized message properties in JCA adapters and Oracle B2B, see Understanding Technology Adapters and User's Guide for Oracle B2B.