我正在尝试在scala上使用xgboost4j spark编译maven项目，但无法消除错误：

object dmlc is not a member of package org.apache.spark.ml
import ml.dmlc.xgboost4j.scala.spark.XGBoostClassifier

我在尝试构建或运行项目时遇到此错误。当我评论导入行时，一切正常。以下是pom.xml内容：

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.test</groupId>
  <artifactId>sparktest</artifactId>
  <version>1.0-SNAPSHOT</version>
  <name>${project.artifactId}</name>
  <description>My wonderful scala app</description>
  <inceptionYear>2018</inceptionYear>
  <licenses>
    <license>
      <name>My License</name>
      <url>http://....</url>
      <distribution>repo</distribution>
    </license>
  </licenses>

  <properties>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
    <encoding>UTF-8</encoding>
    <scala.version>2.11.12</scala.version>
    <scala.compat.version>2.11</scala.compat.version>
    <spec2.version>4.2.0</spec2.version>
    <spark.version>2.4.7</spark.version>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.scala-lang</groupId>
      <artifactId>scala-library</artifactId>
      <version>${scala.version}</version>
    </dependency>

    <!-- Dependencies of Apache Spark 3.X-->
    <dependency>
      <groupId>org.apache.spark</groupId>
      <artifactId>spark-core_${scala.compat.version}</artifactId>
      <version>${spark.version}</version>
    </dependency>

    <dependency>
      <groupId>org.apache.spark</groupId>
      <artifactId>spark-sql_${scala.compat.version}</artifactId>
      <version>${spark.version}</version>
    </dependency>

    <dependency>
      <groupId>org.apache.spark</groupId>
      <artifactId>spark-mllib_${scala.compat.version}</artifactId>
      <version>${spark.version}</version>
    </dependency>

    <!-- XGBoost dependencies /-->
    <!-- https://mvnrepository.com/artifact/ml.dmlc/xgboost4j -->
    <dependency>
      <groupId>ml.dmlc</groupId>
      <artifactId>xgboost4j_${scala.compat.version}</artifactId>
      <version>1.1.2</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/ml.dmlc/xgboost4j-spark -->
    <dependency>
      <groupId>ml.dmlc</groupId>
      <artifactId>xgboost4j-spark_${scala.compat.version}</artifactId>
      <version>1.1.2</version>
    </dependency>
  </dependencies>

  <build>
    <sourceDirectory>src/main/scala</sourceDirectory>
    <testSourceDirectory>src/test/scala</testSourceDirectory>

    <!-- To define the plugin version in your parent POM -->
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>net.alchim31.maven</groupId>
          <artifactId>scala-maven-plugin</artifactId>
          <version>4.4.0</version>
          <executions>
            <execution>
              <goals>
                <goal>compile</goal>
                <goal>testCompile</goal>
              </goals>
            </execution>
          </executions>
          <configuration>
            <scalaVersion>${scala.version}</scalaVersion>
          </configuration>
        </plugin>
      </plugins>
    </pluginManagement>

    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>3.0.0-M4</version>
        <configuration>
          <useFile>false</useFile>
          <disableXmlReport>true</disableXmlReport>
          <useManifestOnlyJar>false</useManifestOnlyJar>
          <includes>
            <include>**/*Test.*</include>
            <include>**/*Suite.*</include>
          </includes>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.scalatest</groupId>
        <artifactId>scalatest-maven-plugin</artifactId>
        <version>2.0.2</version>
        <configuration>
          <reportsDirectory>${project.build.directory}/surefire-reports</reportsDirectory>
          <junitxml>.</junitxml>
          <filereports>TestSuiteReport.txt</filereports>
          <!-- Comma separated list of JUnit test class names to execute -->
          <jUnitClasses>samples.AppTest</jUnitClasses>
        </configuration>
        <executions>
          <execution>
            <id>test</id>
            <goals>
              <goal>test</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <executions>
          <execution>
            <id>copy-dependencies</id>
            <phase>prepare-package</phase>
            <goals>
              <goal>copy-dependencies</goal>
            </goals>
            <configuration>
              <outputDirectory>${project.build.directory}/libs</outputDirectory>
              <overWriteReleases>false</overWriteReleases>
              <overWriteSnapshots>false</overWriteSnapshots>
              <overWriteIfNewer>true</overWriteIfNewer>
            </configuration>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-jar-plugin</artifactId>
        <version>3.2.0</version>
        <configuration>
          <archive>
            <manifest>
              <mainClass>org.test.App</mainClass>
            </manifest>
          </archive>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

这是scala代码：

package org.test

import org.apache.spark._
import org.apache.spark.sql.SparkSession

import ml.dmlc.xgboost4j.scala.spark.XGBoostClassifier
import ml.dmlc.xgboost4j.scala.spark.XGBoostClassificationModel

object App {

  def foo(x : Array[String]) = x.foldLeft("")((a,b) => a + b)

  def main(args : Array[String]) {
    val spark = SparkSession
      .builder()
      .master("local[*]")
      .appName("xgboost")
      .getOrCreate()

    val conf = new SparkConf()
      .setAppName("xgboost")
      .setMaster("local[*]")

    println( "Hello World!" )
    println("concat arguments = " + foo(args))
  }
}

当我在sparkshell中用一个简单的脚本运行代码时，它运行得很好。但是我需要编译jar来使用spark submit。