public <IN, OUT> StreamConfigChainer chain( OperatorID operatorID, OneInputStreamOperator<IN, OUT> operator, TypeSerializer<IN> inputSerializer, TypeSerializer<OUT> outputSerializer) { chainIndex++; tailConfig.setChainedOutputs(Collections.singletonList( new StreamEdge( new StreamNode(null, tailConfig.getChainIndex(), null, null, null, null, null, null), new StreamNode(null, chainIndex, null, null, null, null, null, null), 0, Collections.<String>emptyList(), null, null))); tailConfig = new StreamConfig(new Configuration()); tailConfig.setStreamOperator(checkNotNull(operator)); tailConfig.setOperatorID(checkNotNull(operatorID)); tailConfig.setTypeSerializerIn1(inputSerializer); tailConfig.setTypeSerializerOut(outputSerializer); tailConfig.setChainIndex(chainIndex); chainedConfigs.put(chainIndex, tailConfig); return this; }