multimodal project in intellij can't recognize java nor any main class

Question

I setup simple multi model in community project using java but none of the modules are recognized or complied i have no idea why using on windows 10:

IntelliJ IDEA 2022.3.2 (Community Edition)
Build #IC-223.8617.56, built on January 26, 2023
Runtime version: 17.0.5+1-b653.25 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Windows 10 10.0
GC: G1 Young Generation, G1 Old Generation
Memory: 2048M
Cores: 8
Non-Bundled Plugins:
    Batch Scripts Support (1.0.13)
    CMD Support (1.0.5)
    org.rust.lang (0.4.194.5382-223)
    sandipchitale.springinitializr (1.0.17)
    Docker (223.8617.59)
    dev.flikas.idea.spring.boot.assistant.plugin (222.17.3)

Kotlin: 223-1.8.0-release-345-IJ8617.56

This is how they setup in the IDE :

stock-ui pom

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.stockui</groupId>
    <artifactId>stock-ui</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>
    <name>stockcui</name>
    <description>ui project for Spring Boot</description>

    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </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.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

stockclient pom:

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.stockclient</groupId>
    <artifactId>stockclient</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>
    <name>stockclient</name>
    <description>Demo project for Spring Boot</description>
    
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </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.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

if i build from command line build success but no class are created X

XXXXX MINGW64 /c/dev/my/java/spring_applications/ReactiveSpringBootREST Service2/stockclient/stock-ui
$ mvn clean install -U
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------------< com.stockui:stock-ui >------------------------
[INFO] Building stockcui 1.0-SNAPSHOT
[INFO] --------------------------------[ pom ]---------------------------------
[INFO] 
[INFO] --- maven-clean-plugin:3.3.2:clean (default-clean) @ stock-ui ---
[INFO] 
[INFO] --- spring-boot-maven-plugin:3.2.2:repackage (repackage) @ stock-ui ---
[INFO] 
[INFO] --- maven-install-plugin:3.1.1:install (default-install) @ stock-ui ---
[INFO] Installing C:\dev\my\java\spring_applications\ReactiveSpringBootREST Service2\stockclient\stock-ui\pom.xml to C:\Users\xxxxx\.m2\com\stockui\stock-ui\1.0-SNAPSHOT\stock-ui-1.0-SNAPSHOT.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  1.144 s
[INFO] Finished at: 2024-02-04T12:48:52+02:00
[INFO] ------------------------------------------------------------------------

This is the only class in stock-ui

package com.stockui.stockui;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class StockUIapplication {

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

    }
}

Answer 1

Multimodule projects are typically set up with a root pom.
Take a look at this example:

The root pom would be declared as follows:

Adding modules can be done via:

Visit Project Structure to see your modules:

Compile all modules: