Question

尝试使用Apache Flink使用twitter流并将flatMap转换为case类时，一旦尝试转换tweet，就会失败

java.lang.NoClassDefFoundError: scala/Product$class

版本：

<flink.version>1.7.0</flink.version> <scala.binary.version>2.11</scala.binary.version> <scala.version>2.11.12</scala.version>

已经尝试按照其他几篇文章中的建议更新Scala版本，但是没有用。以下是源代码。

import org.apache.flink.api.common.functions.FlatMapFunction
import org.apache.flink.api.java.utils.ParameterTool
import org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.{JsonNode, ObjectMapper}
import org.apache.flink.streaming.api.scala._
import org.apache.flink.streaming.connectors.twitter.TwitterSource
import org.apache.flink.util.Collector
import org.vj.distributed.Models.Tweet


    object TwitterStreaming {
      def main(args: Array[String]) {
        val env = StreamExecutionEnvironment.getExecutionEnvironment
        val params = ParameterTool.fromArgs(args)
        env.getConfig.setGlobalJobParameters(params)
        env.setParallelism(params.getInt("parallelism", 1))
        val streamSource: DataStream[String] = env.addSource(new TwitterSource(params.getProperties))
        streamSource.flatMap(new ProcessTweetAndPrepareForWrite).print()
        env.execute("TwitterStreaming with Apache Flink")
      }

      private class ProcessTweetAndPrepareForWrite() extends FlatMapFunction[String, Tweet] {
        lazy val jsonParser = new ObjectMapper()
        override def flatMap(value: String, out: Collector[Tweet]): Unit = {
          val jsonNode = jsonParser.readValue(value, classOf[JsonNode])
          val validTweet = jsonNode.has("user") && jsonNode.has("text") && jsonNode.has("geo") &&
            jsonNode.get("user").has("lang") && jsonNode.get("user").get("lang").asText == "en" &&
            jsonNode.get("user").has("followers_count") && jsonNode.get("user").get("followers_count").asInt() > 0 &&
            jsonNode.get("user").has("geo_enabled") && jsonNode.get("user").get("geo_enabled").asBoolean().equals(true) &&
            jsonNode.get("user").has("location") && !jsonNode.get("user").get("location").asText.equalsIgnoreCase("null") &&
            jsonNode.get("geo").has("coordinates") && !jsonNode.get("geo").get("coordinates").asText.equalsIgnoreCase("null")

          (validTweet, jsonNode) match {
            case (true, node) =>
              val location = node.get("user").get("location").asText()
              val followers_count = node.get("user").get("followers_count").asInt()
              val friends_count = if (node.get("user").has("friends_count")) node.get("user").get("friends_count").asInt() else 0
              val geo_enabled = node.get("user").get("geo_enabled").asBoolean()
              val coordinatesArray = node.get("geo").get("coordinates")
              import scala.collection.JavaConversions._
              val latitude = coordinatesArray.head.asText()
              val longitude = coordinatesArray.last.asText()
              val text = jsonNode.get("text").asText()
              out.collect(Tweet(location, followers_count, friends_count, geo_enabled, latitude, longitude, text))
            case _ =>
          }
        }
    }
}

2018-12-24 22：49：41,799 WARN com.twitter.hbc.httpclient.ClientBase
-flink-twitter-source未捕获的异常 java.lang.NoClassDefFoundError：scala / Product $ class 在org.vj.distributed.Models $ Tweet。（Models.scala：5）在org.vj.distributed.TwitterStreaming $ ProcessTweetAndPrepareForWrite.flatMap（TwitterStreaming.scala：45）在org.vj.distributed.TwitterStreaming $ ProcessTweetAndPrepareForWrite.flatMap（TwitterStreaming.scala：23）在org.apache.flink.streaming.api.operators.StreamFlatMap.processElement（StreamFlatMap.java:50）在org.apache.flink.streaming.runtime.tasks.OperatorChain $ CopyingChainingOutput.pushToOperator（OperatorChain.java:579）处在org.apache.flink.streaming.runtime.tasks.OperatorChain $ CopyingChainingOutput.collect（OperatorChain.java:554）在org.apache.flink.streaming.runtime.tasks.OperatorChain $ CopyingChainingOutput.collect（OperatorChain.java:534）在org.apache.flink.streaming.api.operators.AbstractStreamOperator $ CountingOutput.collect（AbstractStreamOperator.java:718）在org.apache.flink.streaming.api.operators.AbstractStreamOperator $ CountingOutput.collect（AbstractStreamOperator.java:696）在org.apache.flink.streaming.api.operators.StreamSourceContexts $ NonTimestampContext.collect（StreamSourceContexts.java:104）处在org.apache.flink.streaming.connectors.twitter.TwitterSource $ 1.process（TwitterSource.java:147）在com.twitter.hbc.httpclient.Connection.processResponse（Connection.java:51）在com.twitter.hbc.httpclient.ClientBase.processConnectionData（ClientBase.java:244）在com.twitter.hbc.httpclient.ClientBase.run（ClientBase.java:144）在java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1149）在java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:624）在java.lang.Thread.run（Thread.java:748）引起原因：java.lang.ClassNotFoundException：scala.Product $ class 在java.net.URLClassLoader.findClass（URLClassLoader.java:382）在java.lang.ClassLoader.loadClass（ClassLoader.java:424）在org.apache.flink.runtime.execution.librarycache.FlinkUserCodeClassLoaders $ ChildFirstClassLoader.loadClass（FlinkUserCodeClassLoaders.java:120）在java.lang.ClassLoader.loadClass（ClassLoader.java:357） ...还有17个

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <flink.version>1.7.0</flink.version>
    <scala.binary.version>2.11</scala.binary.version>
    <scala.version>2.11.12</scala.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.apache.flink</groupId>
        <artifactId>flink-scala_${scala.binary.version}</artifactId>
        <version>${flink.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.flink</groupId>
        <artifactId>flink-streaming-scala_${scala.binary.version}</artifactId>
        <version>${flink.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.scala-lang</groupId>
        <artifactId>scala-library</artifactId>
        <version>${scala.version}</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.flink</groupId>
        <artifactId>flink-connector-twitter_2.11</artifactId>
        <version>1.7.0</version>
    </dependency>
    <dependency>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>org.apache.flink</groupId>
        <artifactId>flink-connector-elasticsearch6_2.11</artifactId>
        <version>1.7.0</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.7</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
        <scope>runtime</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>3.0.0</version>
            <executions>
                <!-- Run shade goal on package phase -->
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <artifactSet>
                            <excludes>
                                <exclude>org.apache.flink:force-shading</exclude>
                                <exclude>com.google.code.findbugs:jsr305</exclude>
                                <exclude>org.slf4j:*</exclude>
                                <exclude>log4j:*</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>
                        <transformers>
                            <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                <mainClass>org.vj.distributed.TwitterStreaming</mainClass>
                            </transformer>
                        </transformers>
                    </configuration>
                </execution>
            </executions>
        </plugin>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>

        <plugin>
            <groupId>net.alchim31.maven</groupId>
            <artifactId>scala-maven-plugin</artifactId>
            <version>3.2.2</version>
            <executions>
                <execution>
                    <goals>
                        <goal>compile</goal>
                        <goal>testCompile</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-eclipse-plugin</artifactId>
            <version>2.8</version>
            <configuration>
                <downloadSources>true</downloadSources>
                <projectnatures>
                    <projectnature>org.scala-ide.sdt.core.scalanature</projectnature>
                    <projectnature>org.eclipse.jdt.core.javanature</projectnature>
                </projectnatures>
                <buildcommands>
                    <buildcommand>org.scala-ide.sdt.core.scalabuilder</buildcommand>
                </buildcommands>
                <classpathContainers>
                    <classpathContainer>org.scala-ide.sdt.launching.SCALA_CONTAINER</classpathContainer>
                    <classpathContainer>org.eclipse.jdt.launching.JRE_CONTAINER</classpathContainer>
                </classpathContainers>
                <excludes>
                    <exclude>org.scala-lang:scala-library</exclude>
                    <exclude>org.scala-lang:scala-compiler</exclude>
                </excludes>
                <sourceIncludes>
                    <sourceInclude>**/*.scala</sourceInclude>
                    <sourceInclude>**/*.java</sourceInclude>
                </sourceIncludes>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>build-helper-maven-plugin</artifactId>
            <version>1.7</version>
            <executions>
                <!-- Add src/main/scala to eclipse build path -->
                <execution>
                    <id>add-source</id>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>add-source</goal>
                    </goals>
                    <configuration>
                        <sources>
                            <source>src/main/scala</source>
                        </sources>
                    </configuration>
                </execution>
                <execution>
                    <id>add-test-source</id>
                    <phase>generate-test-sources</phase>
                    <goals>
                        <goal>add-test-source</goal>
                    </goals>
                    <configuration>
                        <sources>
                            <source>src/test/scala</source>
                        </sources>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

如何解决“'java.lang.NoClassDefFoundError：scala / Product $ class'错误，同时将DataStream映射到Apache Flink中的案例类”

0 个答案: