Celequest user-defined function APIs. Overview This package provides the APIs to add new functions into the Celequest Activity Server. The new functions can be used in view definitions and will be allowed to operate on data that built-in functions operate on. To add an aggregate function you need to implement two interfaces: IUDAggregateFunction and IUDAggregateState. To add a scalar function you need to implement one interface: IUDScalarFunction. NOTES: Instance methods and variables of implementations do not need to be thread-safe whereas static variables and methods must be thread-safe. The use of non-final static variables is strongly discouraged. Any runtime exceptions thrown during the execution of implemented functions will be reported by the Celequest Activity Server.