背景

通常使用flink 提供的高级算子来编写flink 任务，对底层不是很了解，尤其是如何生成作业图的细节
下面通过构造一个有向无环图，来实际看一下

主要步骤

1.增加source
2.增加operator
3. 增加一条边，连接source和operator
4. 增加sink
5. 增加一条边，连接operator和sink

代码

 // Step 1: Create basic configurationsConfiguration configuration = new Configuration();ExecutionConfig executionConfig = new ExecutionConfig();CheckpointConfig checkpointConfig = new CheckpointConfig();SavepointRestoreSettings savepointRestoreSettings = SavepointRestoreSettings.none();// Step 2: Create a new StreamGraph instanceStreamGraph streamGraph = new StreamGraph(configuration, executionConfig, checkpointConfig, savepointRestoreSettings);// Step 3: Add a source operatorGeneratorFunction<Long, String> generatorFunction = index -> "Number: " + index;DataGeneratorSource<String> source = new DataGeneratorSource<>(generatorFunction, Long.MAX_VALUE, RateLimiterStrategy.perSecond(1), Types.STRING);SourceOperatorFactory<String> sourceOperatorFactory = new SourceOperatorFactory<>(source, WatermarkStrategy.noWatermarks());streamGraph.addSource(1, "sourceNode", "sourceDescription", sourceOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "sourceSlot");// Step 4: Add a map operator to transform the dataStreamMap<String, String> mapOperator = new StreamMap<>(new MapFunction<String, String>() {@Overridepublic String map(String value) throws Exception {return value;}});SimpleOperatorFactory<String> mapOperatorFactory = SimpleOperatorFactory.of(mapOperator);streamGraph.addOperator(2, "mapNode", "mapDescription", mapOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "mapSlot");// Step 5: Connect source and map operatorstreamGraph.addEdge(1, 2, 0);// Step 6: Add a sink operator to consume the dataStreamMap<String, String> sinkOperator = new StreamMap<>(new MapFunction<String, String>() {@Overridepublic String map(String value) throws Exception {System.out.println(value);return value;}});SimpleOperatorFactory<String> sinkOperatorFactory = SimpleOperatorFactory.of(sinkOperator);streamGraph.addSink(3, "sinkNode", "sinkDescription", sinkOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "sinkSlot");// Step 7: Connect map and sink operatorstreamGraph.addEdge(2, 3, 0);streamGraph.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);streamGraph.setMaxParallelism(1,1);streamGraph.setMaxParallelism(2,1);streamGraph.setMaxParallelism(3,1);streamGraph.setGlobalStreamExchangeMode(GlobalStreamExchangeMode.ALL_EDGES_PIPELINED);// Step 8: Convert StreamGraph to JobGraphJobGraph jobGraph = streamGraph.getJobGraph();// Step 9: Set up a MiniCluster for local executionMiniClusterConfiguration miniClusterConfig = new MiniClusterConfiguration.Builder().setNumTaskManagers(10).setNumSlotsPerTaskManager(10).build();MiniCluster miniCluster = new MiniCluster(miniClusterConfig);// Step 10: Start the MiniClusterminiCluster.start();// Step 11: Submit the job to the MiniClusterJobExecutionResult result = miniCluster.executeJobBlocking(jobGraph);System.out.println("Job completed with result: " + result);// Step 12: Stop the MiniClusterminiCluster.close();