Question

我有一个Spring Web应用程序（内置于Maven中），通过该应用程序我可以连接到我的spark集群（4个工人和1个master）和cassandra集群（4个节点）。应用程序启动，工作人员与主服务器通信，并且cassandra集群也正在运行。但是，当我通过Web应用程序的界面执行PCA（火花mllib）或任何其他计算（群集，peerson，spearman）时，出现以下错误：

java.lang.ClassCastException：无法将scala.collection.immutable.List $ SerializationProxy的实例分配给scala类型的org.apache.spark.rdd.RDD.org $ apache $ spark $ rdd $ RDD $$ dependencies_字段。 org.apache.spark.rdd.MapPartitionsRDD实例中的collection.Seq

此错误一定是由于spring-boot-maven-plugin和apache spark之间的Jars冲突。

这是我的pom.xml：

<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>app</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>springapp</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
                <maven.compiler.source>1.8</maven.compiler.source>
                <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <version>2.0.9.RELEASE</version>
                    <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
                    <configuration>
                        <requiresUnpack>
                            <dependency>
                                <groupId>org.apache.spark</groupId>
                                <artifactId>spark-core_2.11</artifactId>
                            </dependency>
                            <dependency>
                                <groupId>org.apache.spark</groupId>
                                <artifactId>spark-streaming_2.11</artifactId>
                            </dependency>

                        </requiresUnpack>
                    </configuration>
                </plugin>
              </plugins>
    </build>
        <dependencies>
            <dependency>
                <groupId>org.apache.spark</groupId>
                <artifactId>spark-mllib_2.11</artifactId>
                <version>2.4.3</version>
            </dependency>
            <dependency>
                <groupId>com.datastax.spark</groupId>
                <artifactId>spark-cassandra-connector-unshaded_2.11</artifactId>
                <version>2.4.0</version>
                <exclusions>
                    <exclusion>
                        <groupId>io.netty</groupId>
                        <artifactId>netty-all</artifactId>
                    </exclusion>
                  </exclusions>
            </dependency>
            <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-thymeleaf</artifactId>
                    <version>2.0.9.RELEASE</version>
                    <exclusions>
                        <exclusion>
                          <groupId>org.springframework.boot</groupId>
                          <artifactId>spring-boot-starter-logging</artifactId>
                        </exclusion>
                      </exclusions>
            </dependency>
            <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-web</artifactId>
                    <version>2.0.9.RELEASE</version>
                    <exclusions>
                        <exclusion>
                          <groupId>org.springframework.boot</groupId>
                          <artifactId>spring-boot-starter-logging</artifactId>
                        </exclusion>
                      </exclusions>
            </dependency>
            <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-test</artifactId>
                    <version>2.0.9.RELEASE</version>
                    <scope>test</scope>
                    <exclusions>
                        <exclusion>
                          <groupId>org.springframework.boot</groupId>
                          <artifactId>spring-boot-starter-logging</artifactId>
                        </exclusion>
                      </exclusions>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-cassandra</artifactId>
                <version>2.0.9.RELEASE</version>
            </dependency>
            <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <version>2.0.9.RELEASE</version>
         </dependency>
         <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.5</version>
        </dependency>
         <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.8</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.module</groupId>
            <artifactId>jackson-module-scala_2.11</artifactId>
            <version>2.9.8</version>
        </dependency>
    </dependencies>
</project>

这些是我的网络应用程序的罐子：

您看到会与apache-spark 2.4.3发生冲突的东西，应该从pom中排除吗？

Answer 1

解决了！我只需要更换插件。罐子之间可能存在冲突。

这就是我所拥有的：

            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.0.9.RELEASE</version>
                <executions>
                <execution>
                    <goals>
                        <goal>repackage</goal>
                    </goals>
                </execution>
            </executions>
                <configuration>
                    <requiresUnpack>
                        <dependency>
                            <groupId>org.apache.spark</groupId>
                            <artifactId>spark-core_2.11</artifactId>
                        </dependency>
                        <dependency>
                            <groupId>org.apache.spark</groupId>
                            <artifactId>spark-streaming_2.11</artifactId>
                        </dependency>

                    </requiresUnpack>
                </configuration>
            </plugin>

然后我将其替换为：

<plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.8.0</version>
        <configuration>
            <source>1.8</source>
            <target>1.8</target>
        </configuration>
    </plugin>

和

<plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>2.4.1</version>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.0.9.RELEASE</version>
            </dependency>
        </dependencies>
        <configuration>
            <keepDependenciesWithProvidedScope>true</keepDependenciesWithProvidedScope>
            <createDependencyReducedPom>true</createDependencyReducedPom>
            <filters>
                <filter>
                    <artifact>*:*</artifact>
                    <excludes>
                        <exclude>META-INF/*.SF</exclude>
                        <exclude>META-INF/*.DSA</exclude>
                        <exclude>META-INF/*.RSA</exclude>
                    </excludes>
                </filter>
            </filters>
        </configuration>
        <executions>
            <execution>
                <phase>package</phase>
                <goals>
                    <goal>shade</goal>
                </goals>
                <configuration>
                    <transformers>
                        <transformer
                            implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                            <resource>META-INF/spring.handlers</resource>
                        </transformer>
                        <transformer
                            implementation="org.springframework.boot.maven.PropertiesMergingResourceTransformer">
                            <resource>META-INF/spring.factories</resource>
                        </transformer>
                        <transformer
                            implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                            <resource>META-INF/spring.schemas</resource>
                        </transformer>
                        <transformer
                            implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer" />
                        <transformer
                            implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                            <mainClass>com.example.app.Mtbapp1</mainClass>
                        </transformer>
                    </transformers>
                </configuration>
            </execution>
        </executions>
    </plugin>

春季-Spark：罐子/依赖关系之间的冲突

1 个答案: