Cisco Cisco Unified Customer Voice Portal 10.0(1) Developer's Guide
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and decision elements
DecisionElementBase
, all found in the
com.audium.server.voiceElement
package. These three base classes all extend a common
base class for configurable elements,
ElementBase
.
In order for CVP VoiceXML Studio to identify the Java class representing the actual element (as
opposed to another class lower in the class hierarchy or a standard element that also extends that
class), a “marker” Java interface named
opposed to another class lower in the class hierarchy or a standard element that also extends that
class), a “marker” Java interface named
ElementInterface
must be implemented. Only those
classes that implement this interface are shown in Studio’s Element Pane.
Each configurable element contains a single execution method in which the element performs its
function. This method is called by CVP VoiceXML Server when that element is visited in the
call flow. One can equate this method to the element’s
function. This method is called by CVP VoiceXML Server when that element is visited in the
call flow. One can equate this method to the element’s
main()
method, it begins and ends there.
One argument to the method is an instance of a Session API class. Aside from the standard
functionality available in this class such as obtaining the ANI and setting element data, this API
class can be used to obtain a Java object representing the element’s configuration. The Server
automatically creates this configuration object with the data entered by the application developer
in Studio or made available through a dynamic configuration. The name of the execution method
and the API class passed to it differ for each element type as do the classes encapsulating the
element’s configuration. The execution method for decision and voice elements must return an
exit state and the execution method for action elements do not return anything (since all action
elements explicitly have a single exit state).
functionality available in this class such as obtaining the ANI and setting element data, this API
class can be used to obtain a Java object representing the element’s configuration. The Server
automatically creates this configuration object with the data entered by the application developer
in Studio or made available through a dynamic configuration. The name of the execution method
and the API class passed to it differ for each element type as do the classes encapsulating the
element’s configuration. The execution method for decision and voice elements must return an
exit state and the execution method for action elements do not return anything (since all action
elements explicitly have a single exit state).
The execution method for action and decision elements can throw an
AudiumException
while
voice elements can throw an
ElementException
. The developer would throw this exception if
an error was encountered within the execution method that the developer wishes to end the call.
A call that encountered this exception would then visit the error element (or the application-
specific error message if the error element was not defined), and the error message is placed in
the error log including the exception’s full stack trace.
A call that encountered this exception would then visit the error element (or the application-
specific error message if the error element was not defined), and the error message is placed in
the error log including the exception’s full stack trace.
The base class also includes various methods used to define the element’s configuration. These
methods define everything from the element’s name to its possible exit states. These methods are
essential for CVP VoiceXML Studio to visually render the element and its configuration
correctly. Custom elements will be indistinguishable from CVP VoiceXML Elements within
Studio. The developer can choose as simple or complex a configuration as desired (or even no
configuration at all, though it wouldn’t be very reusable).
methods define everything from the element’s name to its possible exit states. These methods are
essential for CVP VoiceXML Studio to visually render the element and its configuration
correctly. Custom elements will be indistinguishable from CVP VoiceXML Elements within
Studio. The developer can choose as simple or complex a configuration as desired (or even no
configuration at all, though it wouldn’t be very reusable).
Note that element data generated by an element will be overwritten if that same element is
visited again in the call flow. For example, a variable set by a voice element handling the main
menu of an application will be reset the next time the main menu is visited. The activity log,
however, is a historical account of the call, so would have all values of the element data. Should
the developer wish to retain all data created by all visits to the element, they must build that into
the element, such as creating new variables or appending the new value to an existing variable.
visited again in the call flow. For example, a variable set by a voice element handling the main
menu of an application will be reset the next time the main menu is visited. The activity log,
however, is a historical account of the call, so would have all values of the element data. Should
the developer wish to retain all data created by all visits to the element, they must build that into
the element, such as creating new variables or appending the new value to an existing variable.
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