SPL File traceLevelSwitch.spl

com.ibm.streamsx.plumbing > com.ibm.streamsx.plumbing 1.0.0 > com.ibm.streamsx.plumbing.switches > traceLevelSwitch.spl

Content

Operators

• TraceLevelSwitch: Non-blocking switch set by application trace level.

Composites

composite TraceLevelSwitch(output OUT; input IN)

Non-blocking switch set by application trace level.

When the switch is closed all tuples on its input port flow through to its output port unchanged. The switch is closed if isTraceable(traceThreshold) is true or forceClosed is true, otherwise it is open.

When the switch is open tuples on its input port are discarded, thus not blocking any upstream processing.

A change in the application trace level for the PE hosting an invocation of TraceLevelSwitch dynamically changes the state of the switch according to the operator's parameters.

Parameters

• forceClosed: Optional parameter forces this switch to be closed regardless of application trace level. When set to true the switch is closed, otherwise its state is set by the trace level. This parameter is false by default.
• traceThreshold: The application trace level at which this switch closes. Defaults to TraceLevel.trace.

Input Ports

• IN: Input stream to be switched

Output Ports

• OUT: Output stream tuples are submitted to when the switch is closed

SPL Source Code

 public composite TraceLevelSwitch (input IN ; output OUT)
 {
   param 
     expression<boolean> $forceClosed : false;
     expression<Trace.Level> $traceThreshold : Trace.trace;
   graph 
     stream<IN> OUT = Filter(IN) {
       param
         filter : $forceClosed || isTraceable($traceThreshold);
     }
 }