Spring boot multi module project compilation error: cannot find symbol

Question

I created a project with 3 modules:

In kazi-core, i have some entities and enumes and i want to use thoses in api module.

My kazi-core pom.xml:

<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>

    <parent>
        <groupId>com.emo.kazi</groupId>
        <artifactId>kazi</artifactId>
        <version>0.1-SNAPSHOT</version>
    </parent>

    <artifactId>kazi-core</artifactId>
    <version>${parent.version}</version>
    <packaging>jar</packaging>

    <name>kazi-core</name>
    <url>http://maven.apache.org</url>

    <dependencies>
        <dependency>
            <groupId>org.liquibase</groupId>
            <artifactId>liquibase-core</artifactId>
        </dependency>
        <dependency>
            <groupId>org.liquibase</groupId>
            <artifactId>liquibase-maven-plugin</artifactId>
            <version>3.8.2</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

I have one main class in kazi-core module:

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

my kazi-api pom.xml:

<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>

    <parent>
        <groupId>com.emo.kazi</groupId>
        <artifactId>kazi</artifactId>
        <version>0.1-SNAPSHOT</version>
    </parent>

    <artifactId>kazi-api</artifactId>
    <version>${parent.version}</version>
    <packaging>jar</packaging>

    <name>kazi-api</name>
    <url>http://maven.apache.org</url>

    <properties>
        <org.mapstruct.version>1.2.0.Final</org.mapstruct.version>
    </properties>


    <dependencies>
        <dependency>
            <groupId>com.emo.kazi</groupId>
            <artifactId>kazi-core</artifactId>
            <version>${project.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>org.liquibase</groupId>
                    <artifactId>liquibase-core</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-jdk8</artifactId>
            <version>${org.mapstruct.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.7.0</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <verbose>true</verbose>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.mapstruct</groupId>
                            <artifactId>mapstruct-processor</artifactId>
                            <version>${org.mapstruct.version}</version>
                        </path>
                    </annotationProcessorPaths>
                    <compilerArgs>
                        <arg>-Amapstruct.suppressGeneratorTimestamp=true</arg>
                        <arg>-Amapstruct.defaultComponentModel=spring</arg>
                    </compilerArgs>
                </configuration>
            </plugin>
        </plugins>
    </build>

My parent pom.xml:

<parent>
        <groupId>com.emo.kazi</groupId>
        <artifactId>kazi-parent</artifactId>
        <version>1.0-SNAPSHOT</version>
        <relativePath/>
    </parent>

    <artifactId>kazi</artifactId>
    <version>0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>
        <module>build</module>
        <module>kazi-core</module>
        <module>kazi-api</module>
        <module>kazi-service</module>
    </modules>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
    </dependencies>
</project>

i have a parent pom.xml where i defined all the starter dependencies.

by mvn clean install, a lot of symbol cannot find:

Error:(4,30) java: package com.kazi.core.entities does not exist
Error:(12,29) java: cannot find symbol
Error:(14,41) java: cannot find symbol
Error:(17,5) java: cannot find symbol

when i remove:

<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

i don't have any compilation error. But i want to create a runnable jar.

Answer 1

i moved the build tag in the parent pom.xml and added an execution tag to Main class in kazi-core module:

<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                        <configuration>
                            <mainClass>com.emo.core.Application</mainClass>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

i added in kazi-api and kazi-service a build tag and skip the execution:

<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <skip>true</skip>
                </configuration>
            </plugin>
        </plugins>
    </build>

it worked fine.