presto-main/src/main/java/io/prestosql/operator/project/CursorProcessorOutput.java/CursorProcessorOutput/CursorProcessorOutput
class CursorProcessorOutput:    public CursorProcessorOutput(int processedRows, boolean finished)
    {
        checkArgument(processedRows >= 0, "processedRows should be no smaller than 0");
        this.processedRows = processedRows;
        this.finished = finished;
    }