maven

Maven Best Practices

Maven is the definitive build tool for modern Java. Adhere to these rules for consistent, maintainable, and high-quality projects.

Code Organization and Structure

Centralize Configuration with a Parent POM/BOM

Always use a parent POM (or Bill of Materials - BOM) to define shared properties, plugin versions, and a <dependencyManagement> section. This guarantees consistent library versions and build behavior across all modules.

❌ BAD: Duplicating dependency versions and plugin configurations in every child pom.xml.

<!-- child-module/pom.xml -->
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <version>3.2.0</version> <!-- Hardcoded, duplicated -->
    </dependency>
</dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.11.0</version> <!-- Hardcoded, duplicated -->
            <configuration><release>17</release></configuration>
        </plugin>
    </plugins>
</build>

✅ GOOD: Define a parent POM with <dependencyManagement> and <pluginManagement>. Child modules inherit these.

<!-- parent/pom.xml -->
<project>
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.mycompany</groupId>
    <artifactId>my-parent</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>pom</packaging>
    <properties>
        <java.version>17</java.version>
        <spring-boot.version>3.2.0</spring-boot.version>
        <maven.compiler.plugin.version>3.11.0</maven.compiler.plugin.version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>${maven.compiler.plugin.version}</version>
                    <configuration><release>${java.version}</release></configuration>
                </plugin>
            </plugins>
        </pluginManagement>
    </build>
</project>

<!-- child-module/pom.xml -->
<project>
    <parent>
        <groupId>com.mycompany</groupId>
        <artifactId>my-parent</artifactId>
        <version>1.0.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>my-child-module</artifactId>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <!-- Version inherited from parent's dependencyManagement -->
        </dependency>
    </dependencies>
</project>