Implementing getFunctionDescriptors
To create a function descriptor, use the factory class com.apama.dashboard.function.FunctionDescritporFactory. Call createFunctionDescriptor, passing arguments that specify the following:
![*](bullet1.png)
The function name that will be used by the Dashboard Builder and by the implementation of
evaluateFunction![*](bullet1.png)
The argument names that will be used by the Dashboard Builder
![*](bullet1.png)
The argument names that will be used by the implementation of
evaluateFunction![*](bullet1.png)
The return type of the function (
String,
Double,
Integer, or
com.apama.dashboard.data.ITabularData)
![*](bullet1.png)
The names of the returned columns, for functions that return table data
![*](bullet1.png)
A text description of the function
Note: When you create a dashboard custom function you must specify prefixes for parameters according to the parameter type. A prefix must be
s_arg for a
String parameter,
t_arg for a
Table parameter or
i_arg for an
Integer parameter, for example,
s_arg1,
s_arg2. You can see sample code that shows this in the
getFunctionDescriptors() definition near the beginning of
Sample IFunctionLibrary implementation.