When migrating from Ant to Maven, one of the primary tasks is converting the build.xml file to a pom.xml file. While there are tools available to automate this process, understanding how to do it manually can provide more control and insight into the migration process. In this guide, we’ll walk through the steps to manually convert the most common Ant commands to their Maven counterparts.

1. Project Definition

Ant (build.xml):

<project name="MyProject" default="build" basedir=".">

Maven (pom.xml):

<project xmlns="http://maven.apache.org/POM/4.0.0">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example</groupId>
    <artifactId>MyProject</artifactId>
    <version>1.0-SNAPSHOT</version>
</project>

2. Dependencies

Ant: Dependencies in Ant are typically managed using the <path> element and are stored in a lib directory.

Maven: Dependencies are managed in the <dependencies> section. Each dependency is represented by its groupId, artifactId, and version.

<dependencies>
    <dependency>
        <groupId>com.example</groupId>
        <artifactId>library-name</artifactId>
        <version>1.0</version>
    </dependency>
</dependencies>

3. Source and Build Directories

Ant:

<property name="src.dir" value="src"/>
<property name="build.dir" value="build"/>

Maven: By default, Maven assumes the source directory to be src/main/java and the build directory to be target. If you need to change these, you can do so in the <build> section.

4. Compilation

Ant:

<target name="compile">
    <javac srcdir="${src.dir}" destdir="${build.dir}"/>
</target>

Maven: Maven handles compilation automatically when you run mvn compile. However, if you need to customize the compilation process, you can do so using the maven-compiler-plugin.

5. Packaging

Ant:

<target name="jar">
    <jar destfile="MyProject.jar" basedir="${build.dir}"/>
</target>

Maven: Maven handles packaging with the mvn package command. The type of packaging (e.g., jar, war) is specified in the <packaging> element.

<packaging>jar</packaging>

6. Clean

Ant:

<target name="clean">
    <delete dir="${build.dir}"/>
</target>

Maven: Maven’s mvn clean command handles cleaning. It removes the target directory by default.

7. Other Ant Tasks

For other Ant tasks that don’t have a direct Maven counterpart, you can use the maven-antrun-plugin to run Ant tasks within Maven.

Other Example: