Maven

Apache Maven is a software project management and comprehension tool.

Getting Started

Prerequisites

• JRE
  • java -version
• Maven
  • mvn --version

Initialize a project

$ mvn archetype:generate -DgroupId=com.mycompany.app -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.4 -DinteractiveMode=false

What Maven generated for you

my-app

|-- pom.xml

`-- src

|-- main

| `-- java

| `-- com

| `-- mycompany

| `-- app

| `-- App.java

`-- test

`-- java

`-- com

`-- mycompany

`-- app

`-- AppTest.java

• pom.xml: the core of a project's configuration in Maven
• src/main/java: Default Java source folder
• src/test/java: Default Java test folder

Review the generated project files

pom.xml

<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>

<groupId>com.mycompany.app</groupId>

<artifactId>my-app</artifactId>

<version>1.0-SNAPSHOT</version>

<properties>

<maven.compiler.source>1.7</maven.compiler.source>

<maven.compiler.target>1.7</maven.compiler.target>

</properties>

<dependencies>

<dependency>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

<version>4.12</version>

<scope>test</scope>

</dependency>

</dependencies>

</project>

Assemble the library JAR

$ mvn package

...

[INFO] ------------------------------------------------------------------------

[INFO] BUILD SUCCESS

[INFO] ------------------------------------------------------------------------

[INFO] Total time: 2.953 s

[INFO] Finished at: 2019-11-24T13:05:10+01:00

[INFO] ------------------------------------------------------------------------

This is a phase. A phase is a step in the build lifecycle, which is an ordered sequence of phases. When a phase is given, Maven will execute every phase in the sequence up to and including the one defined. For example, if we execute the compile phase, the phases that actually get executed are:

1. validate
2. generate-sources
3. process-sources
4. generate-resources
5. process-resources
6. compile

You may test the newly compiled and packaged JAR with the following command:

$ java -cp target/my-app-1.0-SNAPSHOT.jar com.mycompany.app.App

References

• Maven in 5 Minutes