I am trying to run a project with mixed Kotlin and Java code. We use MapStruct for object mapping, which has no real alternative in Kotlin. Apparently, using MapStruct is possible by using “kapt”. I have a sample project in which I successfully generate a mapper implementation using kapt in kotlin.
Here comes the problem: in our mixed Kotlin/Java project, we use Lombok to annotate Java files. We are aware that Kotlin and Lombok do not work together, and we do not expect them to. We simply want the generated sources from kapt and MapStruct with Kotlin classes, while also using Lombok annotations in the Java classes.
Below is a pom.xml (with a commented Lombok dependency). When we add the Lombok dependency, the build still works but the target/generated-sources folder is empty after a maven install. When we remove the Lombok dependency, target/generated-sources contains a generated Mapper implementation as expected.
<?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>net.foo.bar</groupId>
<artifactId>arti-fact</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<name>Kotlin kapt MapStruct Lombok problem</name>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<kotlin.version>1.3.50</kotlin.version>
<junit.version>4.12</junit.version>
<springfox.version>2.9.2</springfox.version>
<mapstruct.version>1.3.0.Final</mapstruct.version>
<lombok.version>1.18.10</lombok.version>
</properties>
<dependencies>
<!-- Uncomment this to trigger the problem in MapStruct/kapt -->
<!-- <dependency>-->
<!-- <groupId>org.projectlombok</groupId>-->
<!-- <artifactId>lombok</artifactId>-->
<!-- <version>${lombok.version}</version>-->
<!-- </dependency>-->
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib</artifactId>
<version>${kotlin.version}</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-reflect</artifactId>
<version>${kotlin.version}</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib-jdk8</artifactId>
<version>${kotlin.version}</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>${springfox.version}</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>${springfox.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
<groupId>org.projectreactor</groupId>
<artifactId>reactor-spring</artifactId>
<version>1.0.1.RELEASE</version>
</dependency>
<dependency>
<groupId>io.swagger</groupId>
<artifactId>swagger-annotations</artifactId>
<version>1.5.12</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-plugin</artifactId>
<version>${kotlin.version}</version>
</dependency>
<dependency>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct</artifactId>
<version>${mapstruct.version}</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.natpryce</groupId>
<artifactId>hamkrest</artifactId>
<version>1.6.0.0</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-test-junit</artifactId>
<version>${kotlin.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<sourceDirectory>src/main/kotlin</sourceDirectory>
<testSourceDirectory>src/test/kotlin</testSourceDirectory>
<plugins>
<plugin>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<executions>
<execution>
<id>default-compile</id>
<phase>none</phase>
</execution>
<execution>
<id>default-testCompile</id>
<phase>none</phase>
</execution>
<execution>
<id>java-compile</id>
<phase>compile</phase>
<goals>
<goal>compile</goal>
</goals>
</execution>
<execution>
<id>java-test-compile</id>
<phase>test-compile</phase>
<goals>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-maven-plugin</artifactId>
<version>${kotlin.version}</version>
<executions>
<execution>
<id>compile</id>
<phase>process-sources</phase>
<goals>
<goal>compile</goal>
</goals>
</execution>
<execution>
<id>test-compile</id>
<phase>process-test-sources</phase>
<goals>
<goal>test-compile</goal>
</goals>
</execution>
<execution>
<id>kapt</id>
<goals>
<goal>kapt</goal>
</goals>
<configuration>
<sourceDirs>
<sourceDir>src/main/kotlin</sourceDir>
</sourceDirs>
<annotationProcessors>
<annotationProcessor>org.mapstruct.ap.MappingProcessor</annotationProcessor>
</annotationProcessors>
<annotationProcessorPaths>
<annotationProcessorPath>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct-processor</artifactId>
<version>${mapstruct.version}</version>
</annotationProcessorPath>
</annotationProcessorPaths>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
Am I doing anything wrong here, or is this a bug in kapt? If so, can I expect Jetbrains to look at it or should we accept that we cannot use MapStruct and Lombok in the same project?
Potentially relevant sources:
