example of Multi-module maven with Spring Boot

maven, spring, spring-boot

Solution

This question is too simple to answer or too complex to be understood, otherwise I cannot explain why there are no answers.

I would go for a solution that uses a folder structure like the following

project folder
|---pom.xml
|---module1
    |---pom.xml
    |---src
|---module2
    |---pom.xml
    |---src
|---module3
    |---pom.xml
    |---src

I would define the `pom.xml` of the project with a pom packaging, e.g.:

<?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>1.2.7-RELEASE</version>
        <relativePath/>
    </parent>

    <groupId>com.myproject</groupId>
    <artifactId>project</artifactId>
    <packaging>pom</packaging>
    <version>0.0.1-SNAPSHOT</version>

    <modules>
        <module>module1</module>
        <module>module2</module>
        <module>module3</module>
    </modules>

    <name>MySupercoolProject</name>
    <description>What else?</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
      <!-- Put here dependencies shared by your project -->
    </dependencies>
</project>

As you see, the parent of your project will be a `spring-boot-starter-parent`.

Then, the `pom.xml` of one of your modules will be, for instance:

<?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>com.myproject</groupId>
        <artifactId>project</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <groupId>com.myproject</groupId>
    <artifactId>module1</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>

    <name>Application</name>
    <description>SudenGut application</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <start-class>com.myproject.MyApplication</start-class>
        <java.version>1.8</java.version>
        <tomcat.version>8.0.24</tomcat.version>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--- this will not be enough to provide a cool app :) -->
    </dependencies>

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

where the main application is `MyApplication.java` in package `com.myproject` of `module1`.

I would use the jar packaging for the other modules without a main application, unless you have other submodules (i.e., pom packaging again).

Problem

Original source