code: @Override
  	public void collect(final KEY key, final VALUE val) throws IOException {
  		this.outTuple.f0 = key;
  		this.outTuple.f1 = val;
  		this.flinkCollector.collect(outTuple);
  	}
docs: Use the wrapped Flink collector to collect a key-value pair for Flink.
  
  @param key the key to collect
  @param val the value to collect
  @throws IOException unexpected of key or value in key-value pair.