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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>unit_02</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <parent>
        <groupId>org.example</groupId>
        <artifactId>learn-kotlin</artifactId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath>
    </parent>

    <dependencies>
        <!-- see parent pom.xml -->
    </dependencies>

    <properties>
        <mainClass>com.makotojava.learn.kotlin.example2.Example2Kt</mainClass>
    </properties>

    <build>
        <sourceDirectory>src/main/kotlin</sourceDirectory>
        <testSourceDirectory>src/test/kotlin</testSourceDirectory>
        <outputDirectory>target/classes</outputDirectory>
        <plugins>
            <plugin>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-maven-plugin</artifactId>
                <version>${kotlin.version}</version>
                <executions>
                    <execution>
                        <id>compile</id>
                        <goals>
                            <goal>compile</goal> 
                        </goals>
                        <configuration>
                            <sourceDirs>
                                <sourceDir>src/main/kotlin</sourceDir>
                                <sourceDir>src/main/java</sourceDir>
                            </sourceDirs>
                        </configuration>
                    </execution>
                    <execution>
                        <id>test-compile</id>
                        <goals>
                            <goal>test-compile</goal>
                        </goals>
                        <configuration>
                            <sourceDirs>
                                <sourceDir>src/test/kotlin</sourceDir>
                                <sourceDir>src/test/java</sourceDir>
                            </sourceDirs>
                        </configuration>
                    </execution>
                </executions>
                <configuration>
                    <nowarn>true</nowarn>  <!-- Disable warnings -->
                    <args>
                        <arg>-Xjsr305=strict</arg> <!-- Enable strict mode for JSR-305 annotations -->
                    </args>
                </configuration>
            </plugin>  
            <!-- https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-jar-plugin -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>${maven.jar.version}</version>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>${mainClass}</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
            <!-- https://mvnrepository.com/artifact/org.codehaus.mojo/exec-maven-plugin -->
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>${exec.maven.version}</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>java</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <mainClass>${mainClass}</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>