IDEA创建Maven的Scala项目详解

木凡空

7307人浏览 · 2020-06-20 19:56:33

木凡空 · 2020-06-20 19:56:33 发布

一、Windows安装Scala

官网下载：Scala

解压。例如解压到D:\Software\scala-2.13.2
新建系统变量SCALA_HOME，为D:\Software\scala-2.13.2，添加入PATH
cmd打开控制台，查看是否安装成功

二、IDEA配置scala-sdk

在这里插入图片描述

三、创建项目

在这里插入图片描述

四、问题

Failed to execute goal org.scala-tools:maven-scala-plugin:2.15.2:compile(default) on Project DataFus
原因：IDEA的Scala版本与Windows里的Scala版本不兼容。IDEA默认设置的Scala版本为2.7.0，必须修改
解决：

Windows的scala-sdk版本必须大于IDEA设置的scala版本，可Windows安装高版本的Scala或者IDEA设置低版本的Scala
示例是Windows的Scala版本为2.13.2（即scala-sdk-2.13.2），IDEA设置Scala版本为2.11.12

  		<properties>
    		<scala.version>2.11.12</scala.version>
  		</properties>

Failed to execute goal org.scala-tools:maven-scala-plugin:2.15.2:testCompile (default) on project WordCount: wrap: org.apache.commons.exec.ExecuteException: Process exited with an error: 1(Exit value: 1)
解决：

Scala2.9以后就弃用了Application，所以使用2.11版本要用App替代Application，用Main替代App
删除test/scala目录下的MySpec文件

		object Main extends App {
  			println( "Hello World!" )
		}

在这里插入图片描述
3. build.plugins.plugin.version’ for org.scala-tools:maven-scala-plugin is missing. @ line 51, column 15
‘build.plugins.plugin.version’ for org.apache.maven.plugins:maven-eclipse-plugin is missing. @ line 69, column 15
解决：

添加依赖

    <dependency>
     <groupId>org.scala-tools</groupId>
     <artifactId>maven-scala-plugin</artifactId>
     <version>2.11</version>
   </dependency>
   <dependency>
     <groupId>org.apache.maven.plugins</groupId>
     <artifactId>maven-eclipse-plugin</artifactId>
     <version>2.5.1</version>
   </dependency>

设置maven-scala-plugin和maven-eclipse-plugin的版本

        <groupId>org.scala-tools</groupId>
        <artifactId>maven-scala-plugin</artifactId>
        <version>2.11</version>
        
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-eclipse-plugin</artifactId>
        <version>2.5.1</version>

Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
解决：**

设置UTF-8编码

		<properties>
			<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
			<scala.version>2.11.12</scala.version>
		</properties>

完整的POM文件

<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.bing</groupId>
  <artifactId>WordCount</artifactId>
  <version>1.0-SNAPSHOT</version>
  <inceptionYear>2008</inceptionYear>
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <scala.version>2.11.12</scala.version>
  </properties>

  <repositories>
    <repository>
      <id>scala-tools.org</id>
      <name>Scala-Tools Maven2 Repository</name>
      <url>http://scala-tools.org/repo-releases</url>
    </repository>
  </repositories>

  <pluginRepositories>
    <pluginRepository>
      <id>scala-tools.org</id>
      <name>Scala-Tools Maven2 Repository</name>
      <url>http://scala-tools.org/repo-releases</url>
    </pluginRepository>
  </pluginRepositories>

  <dependencies>
    <dependency>
      <groupId>org.scala-lang</groupId>
      <artifactId>scala-library</artifactId>
      <version>${scala.version}</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.4</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.specs</groupId>
      <artifactId>specs</artifactId>
      <version>1.2.5</version>
      <scope>test</scope>
    </dependency>
    
    <!--避免下面的插件出错-->
    <dependency>
      <groupId>org.scala-tools</groupId>
      <artifactId>maven-scala-plugin</artifactId>
      <version>2.11</version>
    </dependency>
    <dependency>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-eclipse-plugin</artifactId>
      <version>2.5.1</version>
    </dependency>
  </dependencies>

  <build>
    <sourceDirectory>src/main/scala</sourceDirectory>
    <testSourceDirectory>src/test/scala</testSourceDirectory>
    <plugins>
      <plugin>
        <groupId>org.scala-tools</groupId>
        <artifactId>maven-scala-plugin</artifactId>
        <version>2.11</version>
        <executions>
          <execution>
            <goals>
              <goal>compile</goal>
              <goal>testCompile</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <scalaVersion>${scala.version}</scalaVersion>
          <args>
            <arg>-target:jvm-1.8</arg>
          </args>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-eclipse-plugin</artifactId>
        <version>2.5.1</version>
        <configuration>
          <downloadSources>true</downloadSources>
          <buildcommands>
            <buildcommand>ch.epfl.lamp.sdt.core.scalabuilder</buildcommand>
          </buildcommands>
          <additionalProjectnatures>
            <projectnature>ch.epfl.lamp.sdt.core.scalanature</projectnature>
          </additionalProjectnatures>
          <classpathContainers>
            <classpathContainer>org.eclipse.jdt.launching.JRE_CONTAINER</classpathContainer>
            <classpathContainer>ch.epfl.lamp.sdt.launching.SCALA_CONTAINER</classpathContainer>
          </classpathContainers>
        </configuration>
      </plugin>
    </plugins>
  </build>
  <reporting>
    <plugins>
      <plugin>
        <groupId>org.scala-tools</groupId>
        <artifactId>maven-scala-plugin</artifactId>
        <configuration>
          <scalaVersion>${scala.version}</scalaVersion>
        </configuration>
      </plugin>
    </plugins>
  </reporting>
</project>