User-Defined External Functions

In CCL projects, use the CREATE LIBRARY statement to call user-defined functions written in C/C++ or Java.

Load C/C++ functions from shared libraries, .so files in Linux and Solaris, and .dll files in Windows. Load Java functions from either .class files or .jar files.

Declare external functions in CCL using the CREATE LIBRARY statement. Once declared, you can use the functions anywhere you use built-in functions.

Scalar functions are supported. Aggregate functions are not supported.

Note: C/C++ external library calls support all ESP datatypes.

Java external library calls support integer, long, float, and string ESP datatypes. In Java, these map respectively to int, long, double, and String. When defining the function in Java, the return and argument datatypes must be written in this format.

Complex types such as dictionaries, vectors, event caches and record types are not supported in external functions.

External C/C++ Function Requirements
External C/C++ functions must conform to the interface of the SAP Sybase Event Stream Processor by following the datatype, argument/return value, and output requirements.
Example: Using External C/C++ Functions
Write a C/C++ function that computes distances to the Event Stream Processor interface. After compiling the function to a shared library, declare it using the CREATE LIBRARY statement, and call the function as needed in your CCL project.
Example: Using Java Functions
Write a Java function that computes distances. After compiling the function as a .class or .jar file, declare it using the CREATE LIBRARY statement, and call the function as needed in your CCL project. Finally, link the library with the Event Stream Processor.
User-Defined SPLASH Functions
Use the SPLASH programming language to write user-defined functions in either global or local declare blocks.

Parent topic: CCL Functions