我正在尝试设置一个 Kafka Connect 接收器，以使用 Datastax 连接器将数据从主题收集到 Cassandra 表中：https://downloads.datastax.com/#akc
运行直接在代理上运行的独立工作线程，运行 Kafka 0.10.2.2-1 ：
name=dse-sink
connector.class=com.datastax.kafkaconnector.DseSinkConnector
tasks.max=1
datastax-java-driver.advanced.protocol.version = V4
key.converter=org.apache.kafka.connect.storage.StringConverter
value.converter=org.apache.kafka.connect.storage.StringConverter
key.converter.schemas.enable=false
value.converter.schemas.enable=false
internal.key.converter=org.apache.kafka.connect.json.JsonConverter
internal.value.converter=org.apache.kafka.connect.json.JsonConverter
internal.key.converter.schemas.enable=false
internal.value.converter.schemas.enable=false
plugin.path=/usr/share/java/kafka-connect-dse/kafka-connect-dse-1.2.1.jar
topics=connect-test
contactPoints=172.16.0.48
loadBalancing.localDc=datacenter1
port=9042
ignoreErrors=true
topic.connect-test.cdrs.test.mapping= kafkakey=key, value=value
topic.connect-test.cdrs.test.consistencyLevel=LOCAL_QUORUM但是我有以下错误：
2019-12-23 16:58:43,165] ERROR Task dse-sink-0 threw an uncaught and unrecoverable exception (org.apache.kafka.connect.runtime.WorkerTask)
java.lang.VerifyError: Bad return type
Exception Details:
Location:
com/fasterxml/jackson/databind/cfg/MapperBuilder.streamFactory()Lcom/fasterxml/jackson/core/TokenStreamFactory; @7: areturn
Reason:
Type 'com/fasterxml/jackson/core/JsonFactory' (current frame, stack[0]) is not assignable to 'com/fasterxml/jackson/core/TokenStreamFactory' (from method signature)
Current Frame:
bci: @7
flags: { }
locals: { 'com/fasterxml/jackson/databind/cfg/MapperBuilder' }
stack: { 'com/fasterxml/jackson/core/JsonFactory' }
Bytecode:
0x0000000: 2ab4 0002 b600 08b0
at com.fasterxml.jackson.databind.json.JsonMapper.builder(JsonMapper.java:114)
at com.datastax.dsbulk.commons.codecs.json.JsonCodecUtils.getObjectMapper(JsonCodecUtils.java:36)
at com.datastax.kafkaconnector.codecs.CodecSettings.init(CodecSettings.java:131)
at com.datastax.kafkaconnector.state.LifeCycleManager.lambda$buildInstanceState$9(LifeCycleManager.java:423)
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
at java.util.HashMap$ValueSpliterator.forEachRemaining(HashMap.java:1625)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
at com.datastax.kafkaconnector.state.LifeCycleManager.buildInstanceState(LifeCycleManager.java:457)
at com.datastax.kafkaconnector.state.LifeCycleManager.lambda$startTask$0(LifeCycleManager.java:106)
at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)
at com.datastax.kafkaconnector.state.LifeCycleManager.startTask(LifeCycleManager.java:101)
at com.datastax.kafkaconnector.DseSinkTask.start(DseSinkTask.java:74)
at org.apache.kafka.connect.runtime.WorkerSinkTask.initializeAndStart(WorkerSinkTask.java:244)
at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:145)
at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:139)
at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:182)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)卡桑德拉或卡夫卡方面没有其他错误。 我在 cassandra 节点上看到活动连接，但没有任何东西到达密钥空间。
知道为什么吗？
恕我直言，这是由于使用带有 BigDecimal 数据的 JSON 内部转换器引起的问题(请参阅相关的 SO 问题(。 如以下博客文章所述，自 Kafka 2.0 以来，internal.key.converter和internal.value.converter已弃用，不应显式设置。 你能注释掉所有internal.属性并重试吗？
附言另请参阅JSON + Decimal 在 Kafka 2.4 中有何变化