The super constructor of implementors of DataFieldChangedListener. DataFieldChangedListeners are notified whenever a data field value is changed in the data source.
dataFieldChanged(value, oldValue, tradeData, updateId)
Notifies listener that the data field value has changed.
Name Type Description
String The value that of the field that was changed.
String The value of the field before the data was changed. This value will be
undefinedif there was no previous value.
Map Map of the values changed in this update.
int Identifier that can be used to determine which update batch this notification belongs to.