Siddhi Function Extension consumes zero or more parameters for each event and output returns a single attribute as an output. This could be used to manipulate event attributes to generate new attribute like attributes synch as the Function operator.
To implement a custom function extension,create a class extending "org.wso2.siddhi.core.executor.function.FunctionExecutor" and create an appropriate .siddhiext extension mapping file, compile the class, and build the jar containing the .class and .siddhiext files. Add them to the Siddhi class path. In a scenario where they are run on WSO2 DAS add the jar to the <DAS_HOME>/repository/components/dropins directory.
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