如何设置IDEA以自动配置Scala facet用于混合Scala/Java Maven项目？

Question

如何让IntelliJ在具有混合Scala和Java源代码的Maven项目中自动配置Scala方面？

我正在使用Scala Plugin Nightly for Maia Build 2099.

mvn compile和mvn test都可以从命令提示符和IntelliJ中的Maven Projects面板进行操作.但是,如果我尝试直接在IntelliJ中运行ScalaSpec,则会出现错误对话框无法使用内容编译Scala文件请在Scala facet中指定编译器.

项目目录结构:

MixedJavaScala
?   MixedScalaJava.iml
?   pom.xml
?
????src
    ????main
    ?   ????java
    ?   ?       HelloJava.java
    ?   ?
    ?   ????scala
    ?           HelloScala.scala
    ?
    ????test
        ????java
        ?       TestJava.java
        ?
        ????scala
                ScalaSpec.scala

HelloJava.java列表:

public class HelloJava {}

HelloScala.scala列表:

class HelloScala

TestJava.java列表:

public class TestJava
{
    @org.junit.Test public void example() {}
}

ScalaSpec.scala列表:

class ScalaSpec extends org.specs.Specification {
  "nothing interesting should happen" in {}
}

pom.xml列表:

<?xml version="1.0" encoding="UTF-8"?>

<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.scala-tools.maven-scala-plugin</groupId>
  <artifactId>MixedScalaJava</artifactId>
  <version>1.0</version>
  <name>Test for Java + Scala compilation</name>
  <description>Test for Java + Scala compilation</description>

  <dependencies>
    <dependency>
      <groupId>org.scala-tools.testing</groupId>
      <artifactId>specs_2.8.0</artifactId>
      <version>1.6.5</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.8.1</version>
    </dependency>
    <dependency>
      <groupId>org.scala-lang</groupId>
      <artifactId>scala-library</artifactId>
      <version>2.8.0</version>
    </dependency>
  </dependencies>
  <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>

  <build>
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>org.scala-tools</groupId>
          <artifactId>maven-scala-plugin</artifactId>
          <version>2.14.1</version>
        </plugin>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>2.3</version>
        </plugin>
      </plugins>
    </pluginManagement>
    <plugins>
      <plugin>
        <groupId>org.scala-tools</groupId>
        <artifactId>maven-scala-plugin</artifactId>
        <executions>
          <execution>
            <id>scala-compile-first</id>
            <phase>process-resources</phase>
            <goals>
                <goal>add-source</goal>
              <goal>compile</goal>
            </goals>
          </execution>
          <execution>
            <id>scala-test-compile</id>
            <phase>process-test-resources</phase>
            <goals>
              <goal>testCompile</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <executions>
          <execution>
            <phase>compile</phase>
            <goals>
              <goal>compile</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <source>1.6</source>
          <target>1.6</target>
        </configuration>
      </plugin>
    </plugins>
  </build>

</project>

Answer 1

一个添加<configuration/>节点到<plugin/>节点Maven的斯卡拉-插件后右<executions/>节点

<configuration>
  <scalaVersion>2.8.0</scalaVersion>
</configuration>

现在,Scala插件会自动检测Scala编译器并自动配置Scala Facet.调试,运行,制作等都可以直接通过IntelliJ接口工作.

它适用于scala-maven-plugin 3.2.0.

请注意,从插件的2.7版开始,要使用的scala版本是从依赖到scala-library的.所以它建议不要使用scalaVersion配置.