Spring Boot Multi Module Gradle Project classpath problem: Package Not Found, Symbol not Found

Question

I have an spring boot gradle project etl with a dependency of common core classes in another project named common.

common/build.gradle

plugins {
    id 'net.ltgt.apt' version '0.21'
    id 'org.springframework.boot'
    id 'io.spring.dependency-management'
    id "io.freefair.lombok" version "5.1.0"
    id 'java'
    id 'idea'
    id 'eclipse'
}

group = 'com.intelease'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    jcenter()
    mavenCentral()
    maven {
        name "lightbend-maven-release"
        url "https://repo.lightbend.com/lightbend/maven-releases"
    }
    maven {
        name "Sonatype Snapshots"
        url "https://oss.sonatype.org/content/repositories/snapshots/"
    }
    ivy {
        name "lightbend-ivy-release"
        url "https://repo.lightbend.com/lightbend/ivy-releases"
        layout "ivy"
    }
}

dependencies {
    implementation 'com.typesafe.play:play-java_2.13:2.7.3'
    implementation 'com.typesafe.akka:akka-actor-typed_2.13:2.5.23'
    implementation "com.typesafe.play:play-guice_2.12:2.6.15"

    implementation 'org.springframework.boot:spring-boot-starter-data-elasticsearch'
    implementation 'org.springframework.boot:spring-boot-starter-data-mongodb-reactive'

    implementation 'org.neo4j.driver:neo4j-java-driver:1.7.5'
    implementation 'org.apache.poi:poi-ooxml:3.17'
    implementation 'com.google.maps:google-maps-services:0.13.0'
    implementation 'org.apache.commons:commons-text:1.8'
    implementation 'com.google.cloud:google-cloud-language:1.19.0'
    implementation 'com.google.cloud:google-cloud-vision:1.19.0'
    implementation 'technology.tabula:tabula:1.0.2'
    implementation 'com.amazonaws:aws-java-sdk:1.11.618'
    implementation 'edu.stanford.nlp:stanford-corenlp:3.8.0'
    implementation 'nz.ac.waikato.cms.weka:weka-stable:3.8.4'
    // https://mvnrepository.com/artifact/com.typesafe.play/play-java
    implementation 'org.joda:joda-money:0.11'
    implementation 'com.feth:play-easymail_2.12:0.9.0'
    implementation 'com.feth:play-authenticate_2.12:0.9.0'
    implementation 'org.apache.commons:commons-imaging:1.0-alpha1'
    implementation 'com.github.cloudyrock.mongock:mongock-core:3.3.2'
    implementation 'com.github.cloudyrock.mongock:mongock-spring:3.3.2'
    implementation 'net.logstash.logback:logstash-logback-encoder:5.3'
    implementation 'ch.qos.logback:logback-core:1.2.3'
    implementation 'ch.qos.logback:logback-classic:1.2.3'
    implementation 'com.google.firebase:firebase-admin:6.13.0'
    implementation 'org.mapstruct:mapstruct:1.3.1.Final'
    implementation 'org.jgrapht:jgrapht-core:1.4.0'
    implementation 'org.jgrapht:jgrapht-io:1.4.0'
    implementation 'commons-io:commons-io:2.6'
    implementation 'org.springframework.guice:spring-guice:1.1.4.RELEASE'
    implementation 'com.google.inject:guice:4.2.3'
    implementation 'commons-collections:commons-collections:3.2.2'
    implementation 'org.aspectj:aspectjrt:1.9.5'
    implementation 'org.ghost4j:ghost4j:1.0.1'
    annotationProcessor 'org.mapstruct:mapstruct-processor:1.3.1.Final'

    testAnnotationProcessor 'org.mapstruct:mapstruct-processor:1.3.1.Final' // if you are using mapstruct in test code

    testImplementation 'io.projectreactor:reactor-test:3.3.0.RELEASE'
    testImplementation 'org.springframework.boot:spring-boot-starter-test:2.2.0.RELEASE'
    testImplementation 'cloud.localstack:localstack-utils:0.1.22'
    testImplementation 'nl.jqno.equalsverifier:equalsverifier:3.3'
    testImplementation 'net.aichler:jupiter-interface:0.8.3'
    testImplementation 'org.mockito:mockito-junit-jupiter:3.0.0'
    testImplementation 'org.assertj:assertj-core:3.13.2'
    testImplementation 'org.junit.jupiter:junit-jupiter-params:5.5.2'
}

etl/settings.gradle:

rootProject.name = 'etl'

includeFlat ('common')

etl/build.gradle:

plugins {
    id 'org.springframework.boot' version '2.2.7.RELEASE'
    id 'io.spring.dependency-management' version '1.0.9.RELEASE'
    id 'eclipse'
    id 'idea'
    id 'java'
}

group = 'com.intelease'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
    mavenCentral()
    jcenter()
    maven {
        name "lightbend-maven-release"
        url "https://repo.lightbend.com/lightbend/maven-releases"
    }
    ivy {
        name "lightbend-ivy-release"
        url "https://repo.lightbend.com/lightbend/ivy-releases"
        layout "ivy"
    }
}

ext {
    set('springCloudVersion', "Hoxton.SR4")
}

dependencies {
    implementation project(':common')
    implementation 'org.apache.kafka:kafka-streams'
    implementation 'io.debezium:debezium-core:1.1.1.Final'
    implementation 'org.springframework.cloud:spring-cloud-stream'
    implementation 'org.springframework.cloud:spring-cloud-stream-binder-kafka-streams'
    testImplementation('org.springframework.boot:spring-boot-starter-test') {
        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
    }


    testImplementation 'org.springframework.cloud:spring-cloud-stream-test-support'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}

test {
    useJUnitPlatform()
}

The etl project and common project are just side by side in the same level in file system.

The problem is that whenever I try to build the etl project which is dependent on common, It shows some problem regarding classes that I've expected to be brought and available from common project.

I've included the common into settings.gradle inside etl project with using includeFlat and Couldn't trace any issue with regard gradle multi module inclusion mechanisms.

Whats wrong with this flat multi module ecosystem?

the build script is ./gradlew clean build in the etl folder.

Answer 1

The problem was because of spring boot plugin being present in both etl and common projects. so I found out that in the cammon/build.gradle I have to add this piece of code:

...

bootJar {
    enabled = false
}

jar {
    enabled = true
}

...