Event Handler Callbacks

The callback information below, in combination with other event handler guidelines, will help you develop event handlers that override or extend standard model behavior.

An event handler performs a mix of custom logic and callbacks to Host Integrator to get information about or modify the state of the model or terminal.

A callback invocation takes place any time an event handler invokes a method on one of the callback interfaces. This may just be asking for information, or it may be a request to modify the model or terminal state.

Note the following properties of callbacks:

Callback Interfaces

The callback interfaces, as documented in the Javadocs for the Event Handler API, are:

  • ScriptHostSession
    Use this interface to get information about the host session and to manipulate the terminal (whether at the terminal, model, or table level).

  • RemoteHostSession
    Use this interface to establish a session with a Host Integrator model other than the one containing this event handler.


  • Callback Limitations