com.ibm.streamsx.topology.function

Interface Initializable

public interface Initializable

Optional interface that a function can implement to perform initialization.

initialize(FunctionContext) is called prior to the function being called to produce or process stream tuples. This will be when:

• the processing element (PE) containing the function starts.
• the PE restarts after a failure or manual request.
• the function is restored from a checkpoint.

Initialization is used open resources that cannot be part of the function's serialized state, such as files or connections to external systems. Custom metrics can also be created using createCustomMetric().
A function that implements this interface may also implement java.lang.AutoCloseable to close any resources opened in initialize(FunctionContext).

Method Summary

Modifier and Type	Method and Description
void	initialize(FunctionContext functionContext) Initialize this function.

Method Detail

initialize

void initialize(FunctionContext functionContext)
         throws java.lang.Exception

Initialize this function.

Parameters:

functionContext - Context the function is executing in.

Throws:

java.lang.Exception - Exception initializing function.