Event Listener

This topic describes an event listener.

In WS-AppServer, an event listener is used to detect any activity that is executed on a BusObject, and apply pre-defined logic on it. In other words, an event listener helps an application developer control the BusObject and its workflow. With the help of an event listener, a developer can define the logic that applies different behaviors to that BusObject and its attributes. When WS-AppServer processes a SOAP request, it confirms the behavior of the BusObject in the form of a SOAP response.
An event listener is used at two levels:

• Object level
  
• Attribute level
  
  An object-level event listener is defined at the object level to handle events that apply to objects. This event listener can be defined as either implicit or explicit.
  
  An attribute-level event listener is defined at the attribute level of an object to handle events that apply on the attributes of an object. This event listener can be defined as either implicit or explicit.