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Apache Flink: java.lang.NoClassDefFoundError

I'm trying to follow this example but when I try to compile it, I have this error:

Error: Unable to initialize main class com.amazonaws.services.kinesisanalytics.aws
Caused by: java.lang.NoClassDefFoundError: org/apache/flink/streaming/api/functions/source/SourceFunction

The error is due this code:

    private static DataStream<String> createSourceFromStaticConfig(StreamExecutionEnvironment env) {
        Properties inputProperties = new Properties();
        inputProperties.setProperty(ConsumerConfigConstants.AWS_REGION, region);
        inputProperties.setProperty(ConsumerConfigConstants.STREAM_INITIAL_POSITION, "LATEST");

        return env.addSource(new FlinkKinesisConsumer<>(inputStreamName, new SimpleStringSchema(), inputProperties));
    }

And I suppose this is the problematic line:

  return env.addSource(new FlinkKinesisConsumer<>(inputStreamName, new SimpleStringSchema(), inputProperties));

This are my maven dependencies:

enter image description here

What could be wrong? any dependencies, version?

Note: If I comment the problematic line, the program run without problem. Also to note, this error also appears on certain Kafka (aws-kafka) samples; I was shown the same error with the amazonaws.kafka.samples.CustomMM2ReplicationPolicy class.

POM file

<?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>as</groupId>
    <artifactId>a</artifactId>
    <version>1</version>
    <packaging>jar</packaging>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <geotools.version>21-SNAPSHOT</geotools.version>
        <java.version>1.8</java.version>
        <scala.binary.version>2.11</scala.binary.version>
        <flink.version>1.6.2</flink.version>
        <kda.version>1.0.1</kda.version>
    </properties>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>

            <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>
                                    <!-- Do not copy the signatures in the META-INF folder.
                                    Otherwise, this might cause SecurityExceptions when using the JAR. -->
                                    <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>com.amazonaws.services.kinesisanalytics.aws</mainClass>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>

    </build>
    <dependencies>
        <dependency>
            <groupId>org.locationtech.jts</groupId>
            <artifactId>jts-core</artifactId>
            <version>1.16.0</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-geojson</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-geojsondatastore</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-main</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-kinesisanalytics-runtime</artifactId>
            <version>${kda.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-kinesis_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-kinesisanalytics-flink</artifactId>
            <version>${kda.version}</version>
        </dependency>
    </dependencies>
</project>
like image 711
IoT user Avatar asked Jan 09 '19 08:01

IoT user


1 Answers

Your error is here:

<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
    <version>${flink.version}</version>
    <scope>provided</scope>
</dependency>

The scope is provided. This means, that your program expects the library to be accessible during the runtime, but it can't find it anywhere.

NoClassDefFoundError means it was accessible during the compile-time, but not during the execution.


Change the scope to compile in order to resolve the issue:

<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
    <version>${flink.version}</version>
    <scope>compile</scope>
</dependency>

Also, you can take a look here for more technical info.

like image 163
aran Avatar answered Oct 28 '22 17:10

aran