Convention over configuration

Convention over configuration is one of the main design philosophies behind Apache Maven. Let's go through a few examples.

A complete Maven project can be created using the following code snippet in pom.xml file:

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.packt</groupId>
  <artifactId>sample-one</artifactId>
  <version>1.0.0</version>
</project>

<project xmlns=http://maven.apache.org/POM/4.0.0xmlns:xsi=………xsi:schemaLocation="…">

Copy the previous configuration element and create a pom.xml file out of it. Then, place it in a directory called chapter-01 and create the following child directories under it:

Now, you can place your Java code under chapter-01/src/main/java and test cases under chapter-01/src/test/java. Use the following command to run the Maven build:

$ mvn clean install

This little configuration is tied up with many conventions:

If someone needs to override the default, conventional behavior of Maven, that is possible too. The following sample pom.xml file shows how to override some of the preceding default values:

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.packt</groupId>
  <artifactId>sample-one</artifactId>
  <version>1.0.0</version>
  <packaging>jar</packaging>

  <build>
    <sourceDirectory>${basedir}/src/main/java</sourceDirectory>
    <testSourceDirectory>${basedir}/src/test/java
    </testSourceDirectory>
    <outputDirectory>${basedir}/target/classes
    </outputDirectory>
  </build>
</project>