Profiles

https://maven.apache.org/guides/introduction/introduction-to-profiles.html
https://maven.apache.org/ref/current/maven-model/maven.html#profiles

profile:
    conditional build configuration

use profile for:
    build-time differences
    repository selection
    plugin execution switch
    package classifier or resource filtering

do not use profile for:
    production secret
    normal application runtime config

<profiles>
  <profile>
    <id>prod</id>
    <properties>
      <build.env>prod</build.env>
    </properties>
  </profile>
</profiles>

./mvnw -Pprod clean package
./mvnw help:active-profiles

<profile>
  <id>coverage</id>
  <activation>
    <property>
      <name>coverage</name>
      <value>true</value>
    </property>
  </activation>
  <build>
    <plugins>
      <plugin>
        <groupId>org.jacoco</groupId>
        <artifactId>jacoco-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</profile>

./mvnw -Dcoverage=true clean verify

<profile>
  <id>jdk21</id>
  <activation>
    <jdk>[21,)</jdk>
  </activation>
  <properties>
    <maven.compiler.release>21</maven.compiler.release>
  </properties>
</profile>

<profile>
  <id>local-extra</id>
  <activation>
    <file>
      <exists>local.properties</exists>
    </file>
  </activation>
</profile>

file activation:
    useful for local-only build behavior
    do not depend on it in CI release jobs

<profile>
  <id>dev</id>
  <activation>
    <activeByDefault>true</activeByDefault>
  </activation>
</profile>

activeByDefault:
    disabled when another profile in the same POM is explicitly activated

./mvnw -Pprod clean package
java -jar app.jar --spring.profiles.active=prod

Maven profile:
    affects build

Spring profile:
    affects runtime application configuration

check:
    profile purpose is build-time
    active profile is visible in CI logs
    profile does not hide required tests
    secrets are not stored in profile properties
    final result is verified with effective-pom