Oracle mediator provides mediation capabilities like transformation, selective routing and validation. It also provides message exchange patterns like synchronous, asynchronous, and event punishing or subscription. It provide a light weight framework for mediation in intra-composite components such as human workflow, business process etc.
Mediator can transform data from one format to another i.e we can give text file data and then after transformation we can send it to database. You can also use mediator component to consume a business event and for receiving service invocation. It helps integration between event and services. You can define rules based on message payload or header in mediator. You can select any attribute to make a routing rule. You can also set execution type of router either parallel or in sequence.