maven build for mixed java and scala

pom.xml

<?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/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>org.yourcompany</groupId>
	<artifactId>ProjectName</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<properties>
		<scalaVersion>2.10.1</scalaVersion>
	</properties>
	<build>
		<plugins>
			<plugin>
				<groupId>org.scala-tools</groupId>
				<artifactId>maven-scala-plugin</artifactId>
				<executions>
				    <!-- force scala compiler to process *.scala & *.java at the same time -->
					<execution>
						<id>scala-compile</id>
						<phase>process-resources</phase>
						<goals>
							<goal>compile</goal>
						</goals>
					</execution>
					<execution>
						<id>scala-testCompile</id>
						<phase>process-test-resources</phase>
						<goals>
							<goal>testCompile</goal>
						</goals>
					</execution>
				</executions>
				<version>2.15.2</version>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.1</version>
				<executions>
					<!-- scala compiler has already compiled *.java -->
					<execution>
						<id>default-compile</id>
						<phase>compile</phase>
						<goals>
							<goal>compile</goal>
						</goals>
						<configuration>
							<skipMain>true</skipMain>
						</configuration>
					</execution>
					<execution>
						<id>default-testCompile</id>
						<phase>test-compile</phase>
						<goals>
							<goal>testCompile</goal>
						</goals>
						<configuration>
							<skip>true</skip>
						</configuration>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
	<dependencies>
		<dependency>
			<groupId>org.scala-lang</groupId>
			<artifactId>scala-library</artifactId>
			<version>${scalaVersion}</version>
		</dependency>
		<dependency>
			<groupId>org.scala-lang</groupId>
			<artifactId>scala-compiler</artifactId>
			<version>${scalaVersion}</version>
		</dependency>
	</dependencies>
</project>