我正在尝试按照本指南集成 Apache Spark Streaming 和 Apache Flume 。我正在尝试在 MapR Sandbox 中进行设置。
当我提交示例时：JavaFlumeEventCount，一切正常，它计算所有事件。我使用一个终端启动 Spark 作业，使用另一个终端启动 Flume。
当我尝试在自己的项目中使用示例代码并创建一个 jar 时，它运行良好，但未计算事件，并且它在 Flume 日志中生成以下异常：
19 Mar 2015 08:32:46,397 ERROR [SinkRunner-PollingRunner-DefaultSinkProcessor] (org.apache.flume.SinkRunner$PollingRunner.run:160) - Unable to deliver event. Exception follows.
org.apache.flume.EventDeliveryException: Failed to send events
at org.apache.flume.sink.AbstractRpcSink.process(AbstractRpcSink.java:392)
at org.apache.flume.sink.DefaultSinkProcessor.process(DefaultSinkProcessor.java:68)
at org.apache.flume.SinkRunner$PollingRunner.run(SinkRunner.java:147)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.flume.EventDeliveryException: NettyAvroRpcClient { host: localhost, port: 8002 }: Failed to send batch
at org.apache.flume.api.NettyAvroRpcClient.appendBatch(NettyAvroRpcClient.java:311)
at org.apache.flume.sink.AbstractRpcSink.process(AbstractRpcSink.java:376)
... 3 more
Caused by: org.apache.flume.EventDeliveryException: NettyAvroRpcClient { host: localhost, port: 8002 }: Exception thrown from remote handler
at org.apache.flume.api.NettyAvroRpcClient.waitForStatusOK(NettyAvroRpcClient.java:393)
at org.apache.flume.api.NettyAvroRpcClient.appendBatch(NettyAvroRpcClient.java:370)
at org.apache.flume.api.NettyAvroRpcClient.appendBatch(NettyAvroRpcClient.java:299)
... 4 more
Caused by: java.util.concurrent.ExecutionException: org.apache.avro.AvroRuntimeException: org.apache.avro.AvroRuntimeException: Unknown datum type: java.lang.ClassCastException: org.apache.avro.generic.GenericData$Record cannot be cast to org.apache.flume.source.avro.AvroFlumeEvent
at org.apache.avro.ipc.CallFuture.get(CallFuture.java:128)
at org.apache.flume.api.NettyAvroRpcClient.waitForStatusOK(NettyAvroRpcClient.java:385)
... 6 more
Caused by: org.apache.avro.AvroRuntimeException: org.apache.avro.AvroRuntimeException: Unknown datum type: java.lang.ClassCastException: org.apache.avro.generic.GenericData$Record cannot be cast to org.apache.flume.source.avro.AvroFlumeEvent
at org.apache.avro.ipc.specific.SpecificRequestor.readError(SpecificRequestor.java:126)
at org.apache.avro.ipc.Requestor$Response.getResponse(Requestor.java:554)
at org.apache.avro.ipc.Requestor$TransceiverCallback.handleResult(Requestor.java:359)
at org.apache.avro.ipc.Requestor$TransceiverCallback.handleResult(Requestor.java:322)
at org.apache.avro.ipc.NettyTransceiver$NettyClientAvroHandler.messageReceived(NettyTransceiver.java:517)
at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
at org.apache.avro.ipc.NettyTransceiver$NettyClientAvroHandler.handleUpstream(NettyTransceiver.java:499)
at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:558)
at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:786)
at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
at org.jboss.netty.handler.codec.frame.FrameDecoder.unfoldAndFireMessageReceived(FrameDecoder.java:458)
at org.jboss.netty.handler.codec.frame.FrameDecoder.callDecode(FrameDecoder.java:439)
at org.jboss.netty.handler.codec.frame.FrameDecoder.messageReceived(FrameDecoder.java:303)
at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:558)
at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:553)
at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:84)
at org.jboss.netty.channel.socket.nio.AbstractNioWorker.processSelectedKeys(AbstractNioWorker.java:471)
at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:332)
at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:35)
at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:102)
at org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
我自己的项目有以下pom.xml：
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>SparkStreamingExample</artifactId>
<version>1.0</version>
<packaging>jar</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-streaming_2.10</artifactId>
<version>1.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-streaming-flume_2.10</artifactId>
<version>1.2.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.3</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<artifactSet>
<excludes>
<exclude>org.apache.spark:spark-streaming_2.10</exclude>
<exclude>org.apache.spark:spark-core_2.10</exclude>
</excludes>
</artifactSet>
<filters>
<filter>
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
为什么它不起作用？