The cascading.operation.Debug function is a utility Function (actually, its a Filter) that will print the current argument Tuple to either stdout or stderr. Used with the DebugLevel enum values NONE, DEFAULT, or VERBOSE, different debug levels can be embedded in a pipe assembly.

Below we insert a Debug operation at the VERBOSE level, but configure the planner to remove all Debug operations from the resulting Flow.

Pipe assembly = new Pipe( "assembly" );

// ...
assembly = new Each( assembly, DebugLevel.VERBOSE, new Debug() );
// ...

Properties properties = new Properties();

// tell the planner remove all Debug operations
FlowConnector.setDebugLevel( properties, DebugLevel.NONE );
// ...
FlowConnector flowConnector = new FlowConnector( properties );

Flow flow = flowConnector.connect( "debug", source, sink, assembly );