Maven - Quick Guide

Maven - Overview

What is Maven?

Maven is a project management and comprehension tool. Maven provides developers a complete build lifecycle framework. Development team can automate the project's build infrastructure in almost no time as Maven uses a standard directory layout and a default build lifecycle.

In case of multiple development teams environment, Maven can set-up the way to work as per standards in a very short time. As most of the project setups are simple and reusable, Maven makes life of developer easy while creating reports, checks, build and testing automation setups.
Maven provides developers ways to manage following:

• Builds
• Documentation
• Reporting
• Dependencies
• SCMs
• Releases
• Distribution
• mailing list

To summarize, Maven simplifies and standardizes the project build process. It handles compilation, distribution, documentation, team collaboration and other tasks seamlessly. Maven increases reusability and takes care of most of build related tasks.

Maven History

Maven was originally designed to simplify building processes in Jakarta Turbine project. There were several projects and each project contained slightly different ANT build files. JARs were checked into CVS.
Apache group then developed Maven which can build multiple projects together, publish projects information, deploy projects, share JARs across several projects and help in collaboration of teams.

Maven Objective

Maven primary goal is to provide developer

• A comprehensive model for projects which is reusable, maintainable, and easier to comprehend.
• plugins or tools that interact with this declarative model.

Maven project structure and contents are declared in an xml file, pom.xml referred as Project Object Model (POM), which is the fundamental unit of the entire Maven system. Refer to Maven POM section for more detail.

Convention over Configuration

Maven uses Convention over Configuration which means developers are not required to create build process themselves.
Developers do not have to mention each and every configuration detail. Maven provides sensible default behavior for projects. When a Maven project is created, Maven creates default project structure. Developer is only required to place files accordingly and he/she need not to define any configuration in pom.xml.
As an example, following table shows the default values for project source code files, resource files and other configurations. Assuming, ${basedir} denotes the project location:

Item	Default
source code	${basedir}/src/main/java
resources	${basedir}/src/main/resources
Tests	${basedir}/src/test
distributable JAR	${basedir}/target
Complied byte code	${basedir}/target/classes

In order to build the project, Maven provides developers options to mention life-cycle goals and project dependencies (that rely on Maven pluging capabilities and on its default conventions). Much of the project management and build related tasks are maintained by Maven plugins.
Developers can build any given Maven project without need to understand how the individual plugins work. Refer to Maven Plug-ins section for more detail.

Maven Environment Setup

Maven is Java based tool, so the very first requirement is to have JDK installed on your machine.

System Requirement

JDK	1.5 or above.
Memory	no minimum requirement.
Disk Space	no minimum requirement.
Operating System	no minimum requirement.

Step 1 - verify Java installation on your machine

Now open console and execute the following java command.

OS	Task	Command
Windows	Open Command Console	c:\> java -version
Linux	Open Command Terminal	$ java -version
Mac	Open Terminal	machine:~ joseph$ java -version

Let's verify the output for all the operating systems:

OS	Output
Windows	java version "1.7.0_75" Java(TM) SE Runtime Environment (build 1.7.0_75-b13) Java HotSpot(TM) Client VM (build 24.75-b04, mixed mode, sharing)
Linux	java version "1.7.0_75" Java(TM) SE Runtime Environment (build 1.7.0_75-b13) Java HotSpot(TM) Client VM (build 24.75-b04, mixed mode, sharing)
Mac	java version "1.7.0_75" Java(TM) SE Runtime Environment (build 1.7.0_75-b13) Java HotSpot(TM)64-Bit Server VM (build 24.75-b04, mixed mode, sharing)

If you do not have Java installed, install the Java Software Development Kit (SDK) from http://www.oracle.com/technetwork/java/javase/downloads/index.html. We are assuming Java 1.7.0_75 as installed version for this tutorial.

Step 2: Set JAVA environment

Set the JAVA_HOME environment variable to point to the base directory location where Java is installed on your machine. For example

OS	Output
Windows	Set the environment variable JAVA_HOME to C:\Program Files\Java\jdk1.7.0_75
Linux	export JAVA_HOME=/usr/local/java-current
Mac	export JAVA_HOME=/Library/Java/Home

Append Java compiler location to System Path.

OS	Output
Windows	Append the string ;C:\Program Files\Java\jdk1.7.0_75\bin to the end of the system variable, Path.
Linux	export PATH=$PATH:$JAVA_HOME/bin/
Mac	not required

Verify Java Installation using java -version command explained above.

Step 3: Download Maven archive

Download Maven 3.3.3 from http://maven.apache.org/download.cgi

OS	Archive name
Windows	apache-maven-3.3.3-bin.zip
Linux	apache-maven-3.3.3-bin.tar.gz
Mac	apache-maven-3.3.3-bin.tar.gz

Step 4: Extract the Maven archive

Extract the archive, to the directory you wish to install Maven 3.3.3. The subdirectory apache-maven-3.3.3 will be created from the archive.

OS	Location (can be different based on your installation)
Windows	C:\Program Files\Apache Software Foundation\apache-maven-3.3.3
Linux	/usr/local/apache-maven
Mac	/usr/local/apache-maven