如何构建需要多个Scala版本的项目？

问题描述

当我尝试通过执行Maven使用spark-ts软件包时

mvn package

发生“ BUILD FAILURE”，出现以下错误。

[INFO] --- scala-maven-plugin:3.2.2:compile (scala-compile-first) @ sparkts ---
[WARNING]  Expected all dependencies to require Scala version: 2.11.4
[WARNING]  com.cloudera.sparkts:sparkts:0.4.0-SNAPSHOT requires scala version: 2.11.4
[WARNING]  com.cloudera.sparkts:sparkts:0.4.0-SNAPSHOT requires scala version: 2.11.4
[WARNING]  org.scala-lang:scalap:2.11.4 requires scala version: 2.11.4
[WARNING]  com.cloudera.sparkts:sparkts:0.4.0-SNAPSHOT requires scala version: 2.11.4
[WARNING]  org.scala-lang:scala-compiler:2.11.4 requires scala version: 2.11.4
[WARNING]  org.scala-lang:scala-reflect:2.11.4 requires scala version: 2.11.4
[WARNING]  org.scala-lang.modules:scala-xml_2.11:1.0.2 requires scala version: 2.11.1
[WARNING] Multiple versions of scala libraries detected!
[INFO] .../spark-timeseries-master/src/main/java:-1: info: compiling
[INFO] .../spark-timeseries-master/src/main/scala:-1: info: compiling
[INFO] Compiling 29 source files to .../spark-timeseries-master/target/classes at 1597272142962
[ERROR] error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
[ERROR] error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
[ERROR]     at scala.reflect.internal.MissingRequirementError$.signal(MissingRequirementError.scala:17)
[ERROR]     at scala.reflect.internal.MissingRequirementError$.notFound(MissingRequirementError.scala:18)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:53)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:66)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getClassByName(Mirrors.scala:102)
[ERROR]     at scala.reflect.internal.Mirrors$RootsBase.getRequiredClass(Mirrors.scala:105)
[ERROR]     at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass$lzycompute(Definitions.scala:257)
[ERROR]     at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass(Definitions.scala:257)
[ERROR]     at scala.reflect.internal.Definitions$DefinitionsClass.init(Definitions.scala:1387)
[ERROR]     at scala.tools.nsc.Global$Run.<init>(Global.scala:1053)
[ERROR]     at scala.tools.nsc.Driver.doCompile(Driver.scala:31)
[ERROR]     at scala.tools.nsc.MainClass.doCompile(Main.scala:23)
[ERROR]     at scala.tools.nsc.Driver.process(Driver.scala:51)
[ERROR]     at scala.tools.nsc.Driver.main(Driver.scala:64)
[ERROR]     at scala.tools.nsc.Main.main(Main.scala)
[ERROR]     at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ERROR]     at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
[ERROR]     at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ERROR]     at java.base/java.lang.reflect.Method.invoke(Method.java:564)
[ERROR]     at scala_maven_executions.MainHelper.runMain(MainHelper.java:164)
[ERROR]     at scala_maven_executions.MainWithArgsInFile.main(MainWithArgsInFile.java:26)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  7.656 s
[INFO] Finished at: 2020-08-12T15:42:24-07:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal net.alchim31.maven:scala-maven-plugin:3.2.2:compile (scala-compile-first) on project sparkts: wrap: org.apache.commons.exec.ExecuteException: Process exited with an error: 1 (Exit value: 1) -> [Help 1]

Error message

我认为问题出在以下事实：scala编译器依赖于scala-xml，这需要较旧版本的scala。有什么办法可以解决多个版本的Scala的问题？

spark-ts的pom文件如下所示。它包括我指定的“依赖项”，但仍然没有解决该问题。 （源代码为here。）

<build>
<plugins>
  <plugin>
    <groupId>org.sonatype.plugins</groupId>
    <artifactId>nexus-staging-maven-plugin</artifactId>
    <version>1.6.7</version>
    <extensions>true</extensions>
    <configuration>
       <serverId>ossrh</serverId>
       <nexusUrl>https://oss.sonatype.org/</nexusUrl>
       <autoReleaseAfterClose>true</autoReleaseAfterClose>
    </configuration>
  </plugin>
  <plugin>
    <groupId>net.alchim31.maven</groupId>
    <artifactId>scala-maven-plugin</artifactId>
    <version>3.2.2</version>
    <configuration>
      <scalaVersion>${scala.complete.version}</scalaVersion>
      <javacArgs>
        <javacArg>-source</javacArg>
        <javacArg>${java.version}</javacArg>
        <javacArg>-target</javacArg>
        <javacArg>${java.version}</javacArg>
      </javacArgs>
    </configuration>
    <executions>
      <execution>
        <phase>compile</phase>
        <goals>
          <goal>compile</goal>
        </goals>
      </execution>
      <execution>
        <id>scala-compile-first</id>
        <phase>process-resources</phase>
        <goals>
          <goal>compile</goal>
        </goals>
      </execution>
      <execution>
        <id>scala-test-compile-first</id>
        <phase>process-test-resources</phase>
        <goals>
          <goal>testCompile</goal>
        </goals>
      </execution>
    </executions>
    <!-- This is what I added to fix the code. But,it still did not work... -->
    <dependencies>
      <dependency>
        <groupId>org.scala-lang.modules</groupId>
        <artifactId>scala-xml_2.11</artifactId>
        <version>1.1.1</version>
      </dependency>
      <dependency>
        <groupId>org.scala-lang.modules</groupId>
        <artifactId>scala-parser-combinators_2.11</artifactId>
        <version>1.1.1</version>
      </dependency>
      <dependency>
        <groupId>org.scala-lang.modules</groupId>
        <artifactId>scala-swing_2.11</artifactId>
        <version>2.0.3</version>
      </dependency>
    </dependencies>
  </plugin>

编辑：将Java 10更改为Java 8后，该问题已解决。

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。

小编邮箱:dio#foxmail.com (将#修改为@）