Starting and Stopping the Record and Playback of Events

Part IV Part IV Extending the Oracle CEP Event Processing Network Part IV contains the following chapters: ■ Chapter 14, Configuring Custom Adapters, ■ Chapter 15, Configuring Custom Event Beans, ■ Chapter 16, Configuring Custom Spring Beans, ■ Chapter 17, Configuring Web Services ■ Chapter 18, Configuring Applications With Data Cartridges ■ Chapter 19, Extending Component Configuration, 14 Configuring Custom Adapters 14-1 14 Configuring Custom Adapters This chapter describes how to code and register custom adapters, including: ■ Section 14.1, Overview of Custom Adapters ■ Section 14.2, Implementing a Custom Adapter ■ Section 14.3, Passing Login Credentials from an Adapter to a Data Feed Provider ■ Section 14.4, Configuring the Custom Adapter EPN Assembly File ■ Section 14.5, Configuring the Custom Adapter Component Configuration File

14.1 Overview of Custom Adapters

One of the main roles of an adapter is to convert data coming from some channel, such as a market data feed, into Oracle CEP events. These events are then passed to other components in the application, such as processors. An adapter is usually the entry point to an Oracle CEP application. An adapter can also be the exit point of an application so that it receives events from an intermediate component, converts the data into something that an external application can read, and then sends it out. Foreign Exchange FX Example in the Oracle Complex Event Processing Getting Started shows three adapters that read in data from currency data feeds and then pass the data, in the form of a specific event type, to the processors, which are the next components in the network. You can create adapters of different types, depending on the format of incoming data and the technology you use in the adapter code to do the conversion. The most typical types of adapters are those that: ■ Use a data vendor API, such as Reuters, Wombat, or Bloomberg. ■ Convert incoming JMS messages using standard JMS APIs. ■ Use other messaging systems, such as TIBCO Rendezvous. ■ Use a socket connection to the customers own data protocol. Adapters are Java classes that implement specific Oracle CEP interfaces. You register the adapter classes in the EPN assembly file that describes your entire application. You can optionally change the default configuration of the adapter, or even extend the configuration and add new configuration elements and attributes. There are two ways to pass configuration data to the adapter; the method you chose depends on whether you want to dynamically change the configuration after deployment: