我是Flink的新手。我正在尝试使用Flink 1.3.2来读取我们的Kinesis流,并将输出写入Cassandra表。该程序能够从Kinesis流式传输数据。
问题是,当我执行“CassandraSink.addSink(CountsStreaming)”时,它给出“类型不匹配。预期: DataStreamNotInferredIN,实际: DataStream(String,Long)”。我已经阅读了文档和源代码,并注意到addSink使用DataStreamIN。
有没有人能帮我理解一下“IN”类型是什么,以及如何解决这个问题?
提前感谢!
val env = StreamExecutionEnvironment.getExecutionEnvironment
val mapper = new ObjectMapper
val kinesis = env.addSource(new FlinkKinesisConsumer[String](
"kinesis-stream", new SimpleStringSchema, ConsumerConfig))
//DataStream[(String, Long)]
val countsStreaming: DataStream[(String, Long)] = kinesis.map(x => mapper.readValue(x,classOf[java.util.Map[String,String]]))
.map(x => x.get("game_name"))
.map({x => (x,1L) })
.keyBy(0)
.timeWindow(Time.seconds(5))
.sum(1)
countsStreaming.print()
CassandraSink.addSink(countsStreaming)
.setQuery("INSERT INTO example.values (id, counter) values (?, ?);")
.setClusterBuilder(new ClusterBuilder() {
override def buildCluster(builder: Cluster.Builder): Cluster = {
builder.addContactPoint("0.0.0.0").build()
}
}).build()
env.execute("StreamingExample")发布于 2018-04-10 17:05:02
问题是CassandraSink.addSink只接受Java DataStream。
您需要在scala DataStream之后添加.javaStream,然后类型不匹配应该会消失。
https://stackoverflow.com/questions/47581521
复制相似问题