Delving deeper into the Adapters, you should know that the Custom JCA Adapter wizard has several purposes:
Customers or third party adapter providers can use the Custom Adapter Wizard "as is" to support their custom runtime adapters. They only need to supply (or extend) the Custom Adapter configuration file (customAdapter-config.xml).
Customers and third party adapter providers can extend the Custom Adapter classes if they want to create a more specific adapter (for example, they can change the text to match their adapter)
The Custom Adapter wizard is a simple example of how to develop a new adapter wizard (or to convert an old adapter wizard) using the JCA Adapter Framework and hooking into the SCAEndpoint interface. After the SOA jdev extension is installed, the Custom Adapter java source files can be found in <JAVA_HOME>/developer/integration/adapters/samples/custom
Before you learn about creating the Adapter design-time components, you need to understand the screens that make up the default Custom Adapter Wizard.