java - 在 Spark 提交期间抛出 NoClassDefFoundError

Question

我正在尝试按如下方式进行 Spark 提交:

spark-submit --class com.subex.roc.apche.spark.IgniteSample 
--master localhost --deploy-mode client spark-0.0.1-SNAPSHOT.jar

以下是项目结构:

将POM文件添加到项目

<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.subex.roc</groupId>
    <artifactId>spark</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>spark</name>
    <url>http://maven.apache.org</url>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-core_2.10</artifactId>
            <version>1.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-sql_2.10</artifactId>
            <version>1.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.ignite</groupId>
            <artifactId>ignite-spark_2.10</artifactId>
            <version>1.5.0.final</version>
        </dependency>
    </dependencies>
</project>

当我运行spark-submit时，它抛出异常:

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/ignite/spark/JavaIgniteContext
    at com.subex.roc.apche.spark.IgniteSample.main(IgniteSample.java:55)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:665)
    at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:170)
    at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:193)
    at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:112)
    at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Caused by: java.lang.ClassNotFoundException: org.apache.ignite.spark.JavaIgniteContext
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 10 more

JavaIgniteContext 是 ignite-spark_2.10 jar 中提供的一个类，它已作为 Maven 依赖项添加。但 Spark 似乎无法在类路径。请帮忙。

Answer 1

您的 JAR 打包后不包含您的依赖项。

将此代码添加到 plugins 部分下的 pom.xml 中:

    <plugins>
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <descriptor>assembly.xml</descriptor>
            </configuration>
        </plugin>
    </plugins>

并将文件 assemble.xml 添加到您的资源目录中:

<assembly xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3 http://maven.apache.org/xsd/assembly-1.1.3.xsd">
    <!-- TODO: a jarjar format would be better -->
    <id>jar-with-dependencies</id>
    <formats>
        <format>jar</format>
    </formats>
    <includeBaseDirectory>false</includeBaseDirectory>
    <dependencySets>
        <dependencySet>
            <outputDirectory>/</outputDirectory>
            <useProjectArtifact>true</useProjectArtifact>
            <unpack>true</unpack>
            <scope>runtime</scope>
        </dependencySet>
    </dependencySets>
</assembly>

然后您可以运行mvn clean clean install或mvn package。

注意:然后您需要使用 jar-with-dependencies 文件作为可运行的 jar。