Apache Maven 2. Part 1: Overview
Getting started with Apache Maven 2
Nikolay Khasanov, Anatoly Kondratyev
October 2012
23 January 2013
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The Goal
• Understand Maven principles
• Build project with Maven
• Compare to Apache Ant
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What is Maven?
GETTING STARTED
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Glossary
• Artifact
• .jar, .ear, .war, .pom, etc.
• GroupId, ArtifactId, Version
• Maven repository
• Holds artifacts
• Dependency
• POM file (Project Object Model)
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What is Maven?
• Build automation tool
• Open Source: Apache License 2.0
• Knowledge accumulator
• Declarative logic instead of imperative
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Maven’s Objectives
• Making the build process easy
• Providing a uniform build system
• Providing quality project information
• Providing guidelines for best practices
development
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Change your mind
CORE MAVEN 2
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Maven project
pom.xml
Project
Dependency
Object
Manager
Model
Project lifecycle Repositories
plug-in plug-in plug-in
source generated resources binary
code code files
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Project Object Model (pom.xml)
project
• Identification groupId
home Spring
2.5.6
• Hierarchy artifactId
version
parentsources
type Junit
• Structure my-app 4.5
classes
Repository
• Dependencies my-app another-app
Servlet
• Build settings API
etc.
2.5
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Super POM
• Package: jar
• Default project structure
• Default artifacts Repository
• Default plugins
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Default folders structure
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Maven does your work
• Store only source code
• Maven knows how to build
• Dependencies are stored in shared
repository
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Transitive dependencies
my-app
dependency.1 dependency.2 dependency.3
dependency.1.1 dependency.1.2
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Dependency scope
Result Compile Runtime Test Lookup
Scope classpath classpath classpath repository
compile + + + +
provided + - + +
runtime - + + +
test - - + +
system + - + -
import Maven 2.0.9 or later, replaces POM with
<dependencyManagement>
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Maven Repository
Local repository External repositories
user local internal external
Central (default)
Maven
User workstation Local network Internet
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Simple Maven project example
MAVEN IN ACTION
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Installation
1. Requirements:
• JRE/JDK 1.4 or higher
2. Download
3. Unzip
4. Setup environment variables:
• M2_HOME
• M2
• PATH
5. Enjoy 
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Configuration
• Global
• <M2_HOME>/conf/settings.xml
• User local
• <USER_HOME>/.m2/settings.xml
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mvn
• mvn [goal(s)] [phase(s)] [options]
• goal = plugin:goal
• phase = phase-name
• Examples:
• mvn compiler:compile
• mvn install –X –DsomeProperty=10
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Build lifecycle
1. validate check pom.xml
2. compile compile the source
3. test run unit tests
4. package create jar/war/...
5. integration-test run integration tests
6. verify verify the package
7. install publish package to local repo
8. deploy publish package to remote repo
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Start-up new project
mvn archetype:create
-DarchetypeGroupId=org.apache.maven.archetypes
-DgroupId=com.exigenservices.training
-DartifactId=myjsf
Result:
• Default folder structure
• pom.xml
• First java class
• First unit-test class
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pom.xml: Minimal POM
<project>
<modelVersion>4.0.0</modelVersion>
<groupId>com.exigenservices.app</groupId>
<artifactId>myjsf</artifactId>
<version>SNAPSHOT</version>
</project>
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pom.xml: Dependencies
<project>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.6</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
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pom.xml: Plug-ins configuration
<project>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.5</source>
<target>1.5</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
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Build project
• mvn install
1. validate
2. compile
3. test
4. package
5. install
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Install and Deploy
deploy
local developer 1
internal
local developer 2
install
…
external
local developer N
Local network Internet
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When deploy is needed?
• Release
• Update snapshot
• Available for other projects
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Add repository
<repositories>
<repository>
<id>Jboss.repository</id>
<url>
http://repository.jboss.org/maven2
</url>
</repository>
</repositories>
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Develop with pleasure!
IDE INTEGRATION
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IDE list
• InteliJ IDEA from 7.0
• Eclipse (plug-in: “m2eclipse”)
• NetBeans 6.5
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IDE features
• POM editor
• Dependency synchronization
• Lifecycle build runners
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Let’s summarize
CONCLUSION
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Advantages (vs. Ant)
• Know Maven – can build project
• Dependency management
• Less CM activities
• Force to standardization
• Readable pom.xml
• High reusability
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Disadvantages (vs. Ant)
• Understanding
• Artifacts search
• Plug-ins documentation
• “Exotic things” - maven-ant-plugin
• Difficult to move from Ant
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Maven repositories
• Central
http://repo1.maven.org/maven2/
• Central repository Explorer
http://mvnrepository.com
• Collection of plugins for Maven 2
http://mojo.codehaus.org
• JBoss
http://repository.jboss.com/maven2/
• Sun
http://download.java.net/maven/2/
• Atlassian
http://repository.atlassian.com/maven2/
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References
• Maven site
http://maven.apache.org
• Quick guide
http://maven.apache.org/guides/MavenQuickReferenceCard.pdf
• Maven FAQ
http://docs.codehaus.org/display/MAVENUSER/FAQs-1
• Better Builds with Maven. John Casey and others
http://www.exist.com/better-build-maven
• Maven overview in Russian
http://www.ibm.com/developerworks/ru/edu/j-mavenv2/index.html
• m2eclipse plug-in
http://m2eclipse.codehaus.org
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Now it’s your turn…
QUESTIONS
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