Hi, How are you bundling your program for execution? Are you, for example, building a fat-jar using Maven? How are you executing the program? Using bin/flink or by executing the program using mvn exec? Also, which Beam/Flink versions are you using?
Best, Aljoscha > On 12. Jun 2017, at 11:28, 基勇 <[email protected]> wrote: > > Hi, > I used beam API to write code to read Kafka data and run with Flink, but > run to throw the following exception: > Caused by: org.apache.flink.streaming.runtime.tasks.StreamTaskException: > Cannot load user class: > org.apache.beam.runners.flink.translation.wrappers.streaming.io.UnboundedSourceWrapper > ClassLoader info: URL ClassLoader: > file: > '/var/folders/vq/887txtm92w508tj7gknjpflc0000gp/T/blobStore-78ed2c9c-03e5-438b-b2ec-514ac394eb11/cache/blob_7123d3372a6822ba044c5ea153ee6801cd5377ff' > (valid JAR) > Class not resolvable through given classloader. > at > org.apache.flink.streaming.api.graph.StreamConfig.getStreamOperator(StreamConfig.java:210) > at > org.apache.flink.streaming.runtime.tasks.OperatorChain.<init>(OperatorChain.java:81) > at > org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:231) > at org.apache.flink.runtime.taskmanager.Task.run(Task.java:665) > at java.lang.Thread.run(Thread.java:745) > > code: > KafkaOptions options = > PipelineOptionsFactory.fromArgs(args).withValidation().as(KafkaOptions.class); > options.setJobName("KafkaExample - WindowSize: " + > options.getWindowSize() + " seconds"); > options.setStreaming(true); > options.setCheckpointingInterval(1000L); > options.setNumberOfExecutionRetries(5); > options.setExecutionRetryDelay(3000L); > options.setRunner(FlinkRunner.class); > > Pipeline pipeline = Pipeline.create(options); > > pipeline.apply(KafkaIO.<String, String>read() > .withBootstrapServers("localhost:9092") > .withTopic(KAFKA_TOPIC) // use > withTopics(List<String>) to read from multiple topics. > .withKeyDeserializer(StringDeserializer.class) > .withValueDeserializer(StringDeserializer.class) > .withoutMetadata() // PCollection<KV<String, > String>> > ).apply(Values.<String> create()); > // .apply(KafkaIO.<Void, String>write() > // .withBootstrapServers("localhost:9092") > // .withTopic(KAFKA_OUTPUT_TOPIC) > // > .withValueSerializer(StringSerializer.class) > // .values()); > > pipeline.run();//.waitUntilFinish(); > > How to fix it ? > > Thank you！
