Apache Maven - eXo TN presentation

APACHE MAVEN APACHE MAVEN APACHE MAVEN Everything about …

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Arnaud Héritier •  eXo - Software Factory Manager

»  In charge of tools and methods

•  Apache Maven : »  Committer since 2004 and member of the

Project Management Committee

•  Coauthor of « Apache Maven » » published by Pearson (in French)

•  Contact me : » http://aheritier.net » Twitter : @aheritier » Skype : aheritier

OVERVIEW Apache Maven

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Definition

•  Apache Maven is a software project management and comprehension tool.

•  Based on the concept of a project object model (POM) » Maven can manage a project's build, binaries,

reporting and documentation from a central piece of information.

•  Apache Maven is standards/conventions driven » How many of you are doing JEE and related

developments ?

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History

•  Initiated in 2001 by Jason Van Zyl in Alexandria, an Apache Jakarta project,

•  Moved to Turbine few months after, •  Became a Top Level Project in 2003. •  Maven 2.0 released in September 2005 •  Maven 3.0 released in October 2010

» 3.0.4 – January 2012

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Choose your way of thinking

Conventions approach Scripting approach

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Competitors

•  Ant + Ivy, Easy Ant, Gant, Gradle, Buildr… •  Script oriented

» You can do what you want ! •  Reuse many of Maven conventions (directories layout, …) and services (repositories) but without enforcing them

•  The risk for them : Not being able to evolve due to the too high level of customization proposed to the user. » We tried on Maven 1 and it died because of that. It was

impossible to create a set of tests to cover all usages. »  It’s like providing a framework without a well tested set of

public API L

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With scripts oriented builds

You can have (if you have good skills)

But often you have (moreover after years …)

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With Maven

We dream to deliver (Maven 3.x)

But yesterday we too often had (Maven 2.x)

CHOOSE YOUR MENU Apache Maven

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Your menu

•  Concepts •  Apache Maven 3.x •  Good and bad practices •  Usecases

CONCEPTS Apache Maven

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Conventions

•  1 project = 1 artifact (pom, jar, war, ear, …) •  Standardized

» project descriptor (POM) » build lifecycle » directories layout

•  *.java to compile in src/[main|test]/java

•  *.xml, *.properties needed in classpath and to bundle in archive in src/[main|test]/resources

•  target directory for generated stuffs (sources, classes, …) •  …

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POM

•  An XML file (pom.xml)

•  Describing » Project identification » Project version » Project description » Build settings » Dependencies » …

<?xml version="1.0" encoding="UTF-8"?>!<project>!

<modelVersion>4.0.0</modelVersion>!

<groupId>net.aheritier.samples</groupId>!

<artifactId>simple-webapp</artifactId>!

<version>1.1-SNAPSHOT</version>!

<packaging>war</packaging>!

<name>Simple webapp</name>!

<inceptionYear>2007</inceptionYear>!

<dependencies>!

<dependency>!

<groupId>org.springframework</groupId>!

<artifactId>spring-struts</artifactId>!

<version>2.0.2</version>!

</dependency>!

...!

</dependencies>!

</project>!

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Reactor

<project>!

...!

<modules>!

<module>moduleA</module>!

<module>moduleB</module>!

<module>moduleC</module>!

<module>moduleD</module>!

<module>moduleE</module> !

<module>moduleF</module>!

</modules>!

...!

</project>!

•  Split your project in sub-modules

•  Maven computes the build order from dependencies between sub-modules.

•  Modules have to be defined in the POM » No auto-discovery for

performance reasons

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Inheritance

•  Share settings between projects/modules

•  By default the parent project is supposed to be in the parent directory (../)

<parent>!

<groupId>net.aheritier.sample</groupId>!

<artifactId>my-parent</artifactId>!

<version>1.0.0-SNAPSHOT<version>!

</parent>!

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Inheritance

Insert README in all artifacts

Use assembly to package batchs

Use clirr to validate backward compatibility

Use a technical inheritance to organize sub-modules

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Artifact Repository

•  By default : » A central repository

•  http://repo1.maven.org/maven2

•  Several dozen of Gb of OSS libraries

» A local repository •  ${user.home}/.m2/repository •  All artifacts

•  Used by maven and its plugins

•  Used by your projects (dependencies)

•  Produced by your projects

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Artifact Repository

•  By default Maven downloads artifacts required by the project or itself from central

•  Downloaded artifacts are stored in the local repository

•  Used to store : » Project’s binaries » Project’s dependencies » Maven and plug-ins

binaries

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Dependencies

Without Maven With Maven

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Dependencies

•  Declaratives » groupId + artifactId + version (+ classifier) » Type (packaging) : jar, war, pom, ear, …

•  Transitives » Lib A needs Lib B » Lib B needs Lib C » Thus Lib A needs Lib C

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Dependencies

•  Scope » Compile (by default) : Required to build and run the application » Runtime : not required to build the application but needed at

runtime •  Ex : taglibs

» Provided : required to build the application but not needed at runtime (provided by the container) •  Ex : Servlet API, Driver SGBD, …

» Test : required to build and launch tests but not needed by the application itself to build and run •  Ex : Junit, TestNG, DbUnit, …

» System : local library with absolute path •  Ex : software products

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Dependencies

•  Define all dependencies you are using » and no more !

•  If you have optional dependencies » Perhaps you should have optional modules

instead •  Cleanup your dependencies with

» mvn dependency:analyze!•  Study your dependencies with

» mvn dependency:tree!» mvn dependency:list!

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Versions

•  Project and dependency versions •  Two different version variants

» SNAPSHOT version •  The version number ends with –SNAPSHOT •  The project is in development •  Deliveries are changing over the time and are overridden

after each build •  Artifacts are deployed with a timestamp on remote

repositories » RELEASE version

•  The version number doesn’t end with –SNAPSHOT •  Binaries won’t change

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Versions

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Versions

•  About SNAPSHOT dependencies » Maven allows the configuration of an update policy.

The update policy defines the recurrence of checks if there is a new SNAPSHOT version available on the remote repository : •  always •  daily (by default) •  interval:X (a given period in minutes) •  never

» Must not be used in a released project •  They can change thus the release also L •  The release plugin will enforce it J

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Versions

•  Range » From … to … » Maven automatically searches for the

corresponding version (using the update policy for released artifacts)

» To use with caution •  Risk of non reproducibility of the build •  Risk of side effects on projects depending on yours.

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Versions

•  Use the versions plugin to update all versions of your project and its modules

mvn versions:set –DnewVersion=A.B.C-SNAPSHOT!

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Profiles

•  Allow to modify the default behavior of Maven by overriding/adding some settings

•  Use mvn help:active-profiles to debug •  Explicit activation or deactivation

mvn <phases or goals> ! -PprofileId1,-profileId2 ! -P!profileId3!

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Profiles

●  activeByDefault = If no other profile is activated

●  Activation through Maven settings <settings>!

...!

<activeProfiles>!

<activeProfile>profile-1</activeProfile>!

</activeProfiles>!

...!

</settings>!

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Profiles

•  Activation based on environment variables

<profiles>!

<profile>!

<activation>!

<property>!

<name>!skip-enforce</name>!

</property>!

</activation>!

...!

</profile>!

</profiles>!

<profiles>!

<profile>!

<activation>!

<property>!

<name>run-its</name>!

<value>true</value>!

</property>!

</activation>!

...!

</profile>!

</profiles>!

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Profiles

•  OS / Java settings <profiles>!

<profile>!

<activation>!

<os>!

<name>Windows XP</name>!

<family>Windows</family>!

<arch>x86</arch>!

<version>5.1.2600</version>!

</os>!

</activation>!

...!

</profile>!

</profiles>!

<profiles>!

<profile>!

<activation>!

<jdk>[1.3,1.6)</jdk>!

</activation>!

...!

</profile>!

</profiles>!

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Profiles

•  Activation on present or missing files <profiles>!

<profile>!

<activation>!

<file>!

<missing>${project.build.directory}/generated-sources/axistools/wsdl2java/</missing>!

</file>!

</activation>!

...!

</profile>!

</profiles>!

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Build Lifecycle And Plugins

•  Plugin based architecture for a great extensibility

•  Standardized lifecycle to build all types of archetypes

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Build Lifecycle And Plugins Default Lifecycle Clean Lifecycle Site Lifecycle validate pre-clean pre-site

initialize clean site generate-sources post-clean post-site

process-sources site-deploy generate-resources

process-resources

compile process-classes

generate-test-sources

process-test-sources

generate-test-resources

process-test-resources

test-compile

process-test-classes

test prepare-package

package pre-integration-test

integration-test

post-integration-test

verify

install deploy

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Build Lifecycle And Plugins

•  Many plugins » Packaging » Reporting » IDE integration » Miscellaneous tools integration

•  Many locations » maven.apache.org » mojo.codehaus.org » code.google.com » …

Take care while selecting them !!!

MAVEN 3.X Apache Maven

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BACKWARD COMPATIBILITY Apache Maven 3.x

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Backward compatibility - Criticisms

•  Migration from Maven 1 to Maven 2 was impossible. Everything had to be re-done.

•  Updates between 2.x versions and also between 2.0.x weren’t often without side effects.

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Backward compatibility

•  Near to 700 integration tests •  Tested for several months on a large set of

OSS projects •  7 alphas + 3 betas versions •  A bug fix release every 6 weeks •  It’s a revolution under the hood but an

evolution for end users

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Maven 3.0.x ITs

674

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PERFORMANCES Apache Maven 3.x

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Performances - Criticisms

•  Maven is slow •  It spends its time to download the world •  Whereas everybody has multicore CPUs, it

doesn’t allow to process modules builds in parallel

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Performances

•  A set of benchmark tools was developed to measure Maven performances (IO, CPU, Memory, Network …)

•  Startup and execution times are reduced » Java 5 optimizations » Code cleanup and improvements

•  Reduced Memory footprint •  Artifacts Resolution Caching

» .lastUpdated files in your local repo » Enforce checks with –U option

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Performances – Parallel builds

•  Parallel builds » An execution plan is predefined at startup to

define which modules could be built in // » Requires to have up to date plugins to avoid dead

locks and some others issues » Launch a build with 2 threads

•  mvn –T 2 install

» Launch a build with 2 threads per CPU core •  mvn –T 2C install

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Performances – mvnsh

•  Performances optimizations » Intelligent cache system (artifacts resolution,

project descriptors …) » No need to restart a JVM for each build

•  Cross platform « unix like » shell » Alias, environment settings … » Color highlighting

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•  All in one » Includes Maven 3.x » Allows to have color highlighting with “standard”

Maven 3.x •  Developed and freely distributed by Sonatype

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EXTENSIBILITY Apache Maven 3.x

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Extensibility - Criticisms

•  It is difficult and time consuming to extend maven (write plugins) » Many unknown technologies like Plexus for IOC

•  It is difficult/impossible to reuse maven plugins » Its impossible to extend plugins/mojo and

lifecycles

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Extensibility

•  New APIs to improve abstraction of underneath implementation » Aether : to manage artifacts and repositories

•  Plugin classloader partitioning •  Embeddable •  IOC replaced by Guice

» For now (3.0) a wrapper is hiding the change » You don’t yet use Guice directly (from plugins for

example)

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ROBUSTNESS Apache Maven 3.x

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Robustness - Criticisms

•  Builds aren’t predictable •  Errors are difficult to diagnose

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Robustness - Validations

•  Many more validations in POMs (warnings or errors) » Missing plugins versions » Duplicated dependencies in a POM » Incoherent inheritance (wrong relative path or

parent not in the upper directory) •  Improved error messages with links to wiki

pages for more detailed information

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Robustness – Artifacts management

•  Parent POMs prefer to resolve from repositories » Version less parent will be available in a future

maven 3.x release by using the relativePath element

•  Profiles usage consolidation » No more profiles.xml (incompatible with future

polyglot feature)

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Robustness – Artifacts management

•  No more support for legacy repository layout for Maven 1.0

•  SNAPSHOTs are always deployed with timestamps

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Robustness – Plugins management

•  Plugin version is by default RELEASE and no more SNAPSHOT » Affects command-line invocation

•  Plugins cannot use versions LATEST or RELEASE » Affects command-line invocation and POM

•  Plugins are resolved only from <pluginRepository> entries

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Robustness – Site plugin

•  Site plugin is now completely extracted from Maven core » It has its own lifecycle » reporting section in POM becomes useless

(moved in plugin configuration)

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POM Apache Maven 3.x

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Criticisms

•  XML, we don’t like it •  POM is too verbose •  POM v4 didn’t evolve last 5 years

» When will you add new common attributes to ease plugins configuration (encoding …)

» New feature like global exclusions

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POM

•  No change in POM syntax for Maven 3.0 •  Changes will occur in 3.x versions

» New model with a new version » Only new things » Generation / deployment of 4.0.0 current POM to

keep backward compatibility with old maven versions

•  Mixins to allow to import POM fragments

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POM - Polyglot

•  Developed and freely distributed by Sonatype •  Extended version of Maven 3.0 using its new

embedding and extensibility capabilities •  Allow translation (read/write) from/to various

syntaxes » Yaml » Scala » Groovy

•  Allow macros and freeform scripting

GOOD & BAD PRACTICES Apache Maven

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KISS Apache Maven

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K.I.S.S.

•  Keep It Simple, Stupid •  Start from scratch

» Do not copy/paste what you find without understanding

•  Use only what you need » It’s not because maven offers many features that you

need to use them •  Filtering •  Modules •  Profiles •  …

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PROJECT ORGANIZATION GOOD & BAD PRACTICES Apache Maven

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Project bad practices

•  Ignore Maven conventions » Except if your are migrating from something else

and the target has to be to follow them. » Except if they are not compatible with your IDE

•  Different versions in sub-modules » In that case they are standalone projects.

•  Too many inheritance levels » It makes the POMs maintenance more complex

•  Where should I set this plugin parameter ? In which parent ?

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Project bad practices

•  Have too many modules » Is there a good reason ?

•  Technical constraint ? •  Team organization ?

» It increases the build time •  Many more artifacts to generate •  Dependencies resolution more complex

» It involves more complex developments •  More modules to import in your IDE •  More modules to update …

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Project good practices

•  Use the default inheritance : » The reactor project is

also the parent of its modules.

» Configuration is easier : •  No need to redefine SCM

settings, site distribution settings …

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POM GOOD & BAD PRACTICES Apache Maven

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POM bad practices

•  Dependencies : » DON’T confuse dependencies and

dependencyManagement •  Plugins :

» DON’T confuse plugins and pluginManagement » DON’T use AntRun plugin everywhere » DON’T let Maven choose plugins versions for you

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POM bad practices

•  Profiles : » DON’T create environment dependant builds » DON’T rely on dependencies coming from profiles

(there is no transitive activation of profiles) •  Reporting and quality

» DON’T activate on an existing project all reports with default configuration

» DON’T control formatting rules without giving settings for IDEs.

•  DON’T put everything you find in your POM.

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POM good practices

•  Set versions of dependencies in project parent’s dependencyManagement

•  Set dependencies (groupId, artifactId, scope) in each module they are used

•  Use the dependency plugin (from apache) and versions plugin (from mojo) to analyze, cleanup and update your dependencies.

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DEVELOPMENT GOOD & BAD PRACTICES Apache Maven

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Development bad practices

•  DON’T spend your time in the terminal, •  DON’T exchange libraries through emails, •  DON’T always use "-Dmaven.test.skip=true” •  DON’T manually do releases

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Development good practices

•  Keep up-to-date your version of Maven » For example in 2.1 the time of dependencies/modules

resolution decreased a lot (Initialization of a project of 150 modules passed from 8 minutes to less than 1)

•  Use the reactor plugin (Maven < 2.1) or native reactor command line options (Maven >= 2.1) to rebuild only a subpart of your project : » All modules depending on module XXX » All modules used to build XXX

•  Try to not use Maven features not supported by your IDE (resources filtering with the plugin eclipse:eclipse)

USECASES Apache Maven

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SECURE YOUR CREDENTIALS Apache Maven

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Secure your credentials

-  arnaud@leopard:~$ mvn --encrypt-master-password toto{dZPuZ74YTJ0HnWHGm4zgfDlruYQNda1xib9vAVf2vvY=}!

l  Generate a private key

<settingssecurity>!

<master>{dZPuZ74YTJ0HnWHGm4zgfDlruYQNda1xib9vAVf2vvY=}</master>!

</settingssecurity>!

●  We save the private key in ~/.m2/settings-security.xml

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Secure your credentials

-  <settingsSecurity> <relocation>/Volumes/ArnaudUsbKey/secure/settings-security.xml</relocation></settingsSecurity>!

●  You can move this key to another drive ~/.m2/settings.xml

●  You create an encrypted version of your server password

-  arnaud@mbp-arnaud:~$ mvn --encrypt-password titi{SbC9Fl2jA4oHZtz5Fcefp2q1tMXEtBkz9QiKljPiHss=}!

●  You register it in your settings

-  <settings> ... <servers> ... <server> <id>mon.server</id> <username>arnaud</username> <password>{SbC9Fl2jA4oHZtz5Fcefp2q1tMXEtBkz9QiKljPiHss=}</password> </server> ... </servers> ...</settings>!

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BUILD A PART OF YOUR PROJECT Apache Maven

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Using Reactor Options

•  Options added in maven 2.1 •  Available in 2.0.x with the maven-reactor-

plugin » But syntax is longer

•  Allow to control what you want to build in your project

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-  arnaud@mbp-arnaud:~$ mvn install[INFO] ------------------------------------------------[INFO] Reactor Summary:[INFO][INFO] Project ....................... SUCCESS [2.132s][INFO] ModuleA ....................... SUCCESS [5.574s][INFO] ModuleB ....................... SUCCESS [0.455s][INFO] ModuleC ....................... SUCCESS [0.396s][INFO] ModuleD ....................... SUCCESS [0.462s][INFO] ModuleE ....................... SUCCESS [0.723s][INFO] ModuleF ....................... SUCCESS [0.404s]!

l  Builds everything from A to F

- arnaud@mbp-arnaud:~$ mvn installarnaud@mbp-arnaud:~$ mvn install[INFO] ------------------------------------------------[INFO] Reactor Summary:[INFO][INFO] Project ....................... SUCCESS [INFO][INFO] Project ....................... SUCCESS [INFO]

[2.132s][INFO] ModuleA ....................... SUCCESS [5.574s][INFO] ModuleB ....................... SUCCESS [0.455s][INFO] ModuleC ....................... SUCCESS [0.396s][INFO] ModuleD ....................... SUCCESS [0.462s][INFO] ModuleE ....................... SUCCESS [0.723s][INFO] ModuleF ....................... SUCCESS [0.404s]

l Builds everything from A to F

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-  arnaud@mbp-arnaud:~$ mvn install –pl moduleE,moduleB[INFO] -------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleB .................. SUCCESS [2.774s][INFO] ModuleE .................. SUCCESS [1.008s]!

l  Builds only modules B and E l  Following dependencies order l  -pl --project-list: Build the

specified reactor projects instead of all projects

- arnaud@mbp-arnaud:~$ mvn install moduleE,moduleBarnaud@mbp-arnaud:~$ mvn install moduleE,moduleBarnaud@mbp-arnaud:~$ mvn install

[INFO] -------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleB .................. SUCCESS [2.774s][INFO] ModuleE .................. SUCCESS [1.008s]

l Builds only modules B and E l Following dependencies order l -pl --project-list:

specified reactor projects instead -pl --project-list: specified reactor projects instead -pl --project-list: of all projectsspecified reactor projects instead of all projectsspecified reactor projects instead

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-  arnaud@mbp-arnaud:~$ mvn install –pl moduleD -am[INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleA ................. SUCCESS [4.075s][INFO] ModuleB ................. SUCCESS [0.468s][INFO] ModuleC ................. SUCCESS [0.354s][INFO] ModuleD ................. SUCCESS [0.384s]!

l  Builds module D (-pl) and all modules it uses as dependencies

l  -am --also-make: If a project list is specified, also make projects that the list depends on

l  Usecase : Build all modules required for a war, ear, …

- arnaud@mbp-arnaud:~$ mvn install [INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleA ................. SUCCESS [4.075s][INFO] ModuleB ................. SUCCESS [0.468s][INFO] ModuleC ................. SUCCESS [0.354s][INFO] ModuleD ................. SUCCESS [0.384s]

l Builds module D (-pl) and all modules it uses as Builds module D (-pl) and all modules it uses as Builds module D (-pl) and all

dependencies l -am --also-make:

is specified, also make projects that the list depends on is specified, also make projects that the list depends on is specified, also make projects

l Usecase required for a war, ear,

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-  arnaud@mbp-arnaud:~$ mvn install –pl moduleD -amd[INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleD ................. SUCCESS [4.881s][INFO] ModuleE ................. SUCCESS [0.478s][INFO] ModuleF ................. SUCCESS [0.427s]!

l  Builds module D (-pl) and all modules which depend on it

l  -amd --also-make-dependents: If a project list is specified, also make projects that depend on projects on the list

l  Usecase : Check that a change in a module didn’t break others which are using it

- arnaud@mbp-arnaud:~$ mvn install [INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleD ................. SUCCESS [4.881s][INFO] ModuleE ................. SUCCESS [0.478s][INFO] ModuleF ................. SUCCESS [0.427s]

l Builds module D (-pl) and all modules which depend on it Builds module D (-pl) and all modules which depend on it Builds module D (-pl) and all

l -amd --also-make-dependents: If a project list is specified, also -amd --also-make-dependents: If a project list is specified, also -amd --also-make-dependents: make projects that depend on If a project list is specified, also make projects that depend on If a project list is specified, also

projects on the list make projects that depend on projects on the list make projects that depend on

l Usecase in a module didn’t break others which are using it

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-  arnaud@mbp-arnaud:~$ mvn install –rf moduleD[INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleD ................. SUCCESS [9.707s][INFO] ModuleE ................. SUCCESS [0.625s][INFO] ModuleF ................. SUCCESS [0.679s] [INFO] Project ................. SUCCESS [2.467s]!

l  Restarts all the build from module D (-rf)

l  -rf,--resume-from <arg> : Resume reactor from specified project

l  Usecase : The build failed a 1st time in module D, you fixed it, and restart the build were it was to end it.

- arnaud@mbp-arnaud:~$ mvn install [INFO] ------------------------------------------[INFO] Reactor Summary:[INFO][INFO] ModuleD ................. SUCCESS [9.707s][INFO] ModuleE ................. SUCCESS [0.625s][INFO] ModuleF ................. SUCCESS [0.679s] [INFO] Project ................. SUCCESS [2.467s][INFO] ModuleF ................. SUCCESS [0.679s] [INFO] Project ................. SUCCESS [2.467s][INFO] ModuleF ................. SUCCESS [0.679s]

l Restarts all the build from module D (-rf)

l -rf,--resume-from <arg> :Resume reactor from specified -rf,--resume-from <arg> :Resume reactor from specified -rf,--resume-from <arg> :project Resume reactor from specified project Resume reactor from specified

l Usecase time in module D, you fixed it, and restart the build were it was time in module D, you fixed it, and restart the build were it was time in module D, you fixed it,

to end it.

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RELEASE YOUR PROJECT Apache Maven

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Release of a webapp in 2002

•  Limited usage of eclipse » No WTP (Only some features in WSAD), » No ability to produce WARs

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•  Many manual tasks » Modify settings files » Package JARs » Copy libraries (external and internal) in a « lib »

directory » Package WAR (often with a zip command) » Tag the code (CVS) » Send the package on the integration server using

FTP » Deploy the package with AS console

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•  One problem : The are always problems » Error in config files » Missing dependencies »  Missing file »  Last minute fix which created a

bug »  And many other possibilies ..

•  How long did it take ? » When everything is

ok : 15 minutes » When there’s a

problem : ½ day or more

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Maven Release Plugin

•  Automates the release process from tagging sources to binaries delivery

•  Release plugin main goals: » Prepare : To update maven versions and

information in POMs and tag the code » Perform : To deploy binaries in a maven

repository •  After that you can just automate the

deployment on the AS using cargo for example.

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Maven Release Plugin

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Configuration and Prerequisites

•  Project version (must be a SNAPSHOT version)

•  Dependencies and plugins versions mustn’t be SNAPSHOTs

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Troubleshooting Releases

•  Common errors during release: » Build with release profile was tested before and

fails » Local modifications » Current version is not a SNAPSHOT » SNAPSHOTs in dependencies and/or plugins » Missing some configuration (scm, distribMgt, …) » Tag already exists » Unable to deploy project to the Repository » Connection problems

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SCM configuration

SCM binaries have to be in the PATH SCM credentials have to already be stored or

you have to pass them in command line with : –Dusername=XXX –Dpassword=XXX

<scm>! <connection>scm:svn:http://svn.acme.com/myproject/trunk</connection>! <developerConnection>scm:svn:https://svn.acme.com/myproject/trunk</developerConnection>! <url>http://fisheye.acme.com/browse/myproject/trunk</url>!</scm>!

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Distribution Management

•  Where you want to upload released binaries » The url of a repository dedicated for your project/

corporate maven deliveries in your repository manager

<project>! <distributionManagement>! <repository>! <id>repository.acme.com</id>! <url>${acme.releases.repo.url}</url>! </repository>! . . .! </distributionManagement>! . . . ! <properties>! <acme.releases.repo.url>http://repo.acme.com/acme-releases</acme.releases.repo.url>! . . .! </properties>!</project>!

This id will be used in user’s maven settings (~/.m2/settings.xml)

Often useful to have a property to test the release process on a fake repository, to validate a repo manager ...

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Repository credentials

•  One server entry is required per different repository id in distribution management of projects

•  In a corporate environment, use a unique id for all repositories hosted on repository managers using same credentials (corporate LDAP …)

<settings>! ...! <servers>! <server>! <id>repository.acme.com</id>! <username>aheritier</username>! <password>{ABCDEFGHIJKLMNOPQRSTUVWYZ}</password>! </server>! ...! </servers>! ...!</settings>!

<password>{ABCDEFGHIJKLMNOPQRSTUVWYZ}</password>This id is the one defined in distributionManagement entry of the project to release

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Default Release Profile in Super POM

•  This profile is used when you generate binaries of the release with “mvn release:perform”

•  By default, generates sources and javadocs jars for each module.

<profile>! <id>release-profile</id>! <activation>! <property>! <name>performRelease</name>! <value>true</value>! </property>! </activation>! <build>! <plugins>! ...! </plugins>! </build>!</profile>!

Configuration to generate sources and javadoc jars with basic setting

This activation could be used in profiles you want to activate in the release process

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Custom release profile

<project>! ...! <build>! <pluginManagement>! <plugins>! <plugin>! <groupId>org.apache.maven.plugins</groupId>! <artifactId>maven-release-plugin</artifactId>! <version>2.0</version>! <configuration>! <useReleaseProfile>false</useReleaseProfile>! <releaseProfiles>myreleaseprofile</

releaseProfiles>! </configuration>! </plugin>! </plugins>! </pluginManagement>! </build>! ...! <profiles>! <profile>! <id>myreleaseprofile</id>! <build>! ...! </build>! </profile>! </profiles>! ...!</project>!

Customize the behavior of the build for a release Take care to test is before the release !!

Use our customized profile Use our customizedDon’t use the default profile

Our customized profile

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SETUP A GLOBAL MIRROR Apache Maven

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Why should we setup a global mirror ?

•  To simplify users and projects settings •  To control where binaries are coming from

» To not rely on project’s repositories » To use only the corporate repository manager

•  To improve build performances » By reducing the number of requests to find a

missing artefact

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How should we setup a global mirror ?

<setting> <mirrors> <mirror> <id>global-mirror</id> <mirrorOf>external:*</mirrorOf> <url>http://repo.acme.com/public</url> </mirror> </mirrors> <profiles> <profile> <id>mirror</id> <repositories> <repository> <id>central</id> <url>http://central</url> <releases><enabled>true</enabled></releases> <snapshots><enabled>true</enabled></snapshots> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>central</id> <url>http://central</url> <releases><enabled>true</enabled></releases> <snapshots><enabled>true</enabled></snapshots> </pluginRepository> </pluginRepositories> </profile> </profiles> <activeProfiles> <activeProfile>mirror</activeProfile> </activeProfiles></settings> !

<url>http://repo.acme.com/public</url> Send all requests to this url

Enable snapshots

make the profile active all the time

<releases><enabled>true</enabled></releases> <snapshots><enabled>true</enabled></snapshots>

Enable snapshots

Use « central » id to override default maven configuration

TO GO FURTHER … Apache Maven

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IDE Apache Maven

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Eclipse

•  Integration from maven (eclipse:eclipse) » Allow many customizations » Support many versions/variants of eclipse » Support many usages (ear …) » Doesn’t support projects with “pom” packaging » Few support from dev team » Many bugs in classpath management » Asynchronous

•  You have to regenerate and reload project each time you change a POM)

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Eclipse

•  Integration from eclipse (m2eclipse) » Synchronous » Nice UI and services to edit POMs » Support projects with “pom” packaging » Doesn’t support all usages like EAR with WTP » Doesn’t support very well a large number of

modules » Slow down eclipse on large projects because of a

lack of support of incremental build in Maven 2.x and its plugins

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Eclipse (m2eclipse)

109

Eclipse (m2eclipse)

110

Eclipse (m2eclipse)

111

Idea IntelliJ

112

Netbeans

113

COMMUNITY Apache Maven

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Users Mailing List

•  Blue : » Number of subscribers

•  Red : » Number of messages

per day

•  [email protected] » Traffic statistics cover a

total of 2025 days. » Current subscribers: 1936 » Current digest

subscribers: 48 » Total posts (2025 days):

89687 » Mean posts per day:

44.29 •  http://pulse.apache.org/

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Apache Maven Web Site

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Dowloads

Per month downloads http://people.apache.org/~vgritsenko/stats/

projects/maven.html

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The team

•  60 committers, •  More than 30 active in 2009, •  Several organizations like Sonatype, deliver

resources and professional support, •  A community less isolated : more interactions

with Eclipse, Jetty,

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Commit Statistics

•  In light blue the number of active commiters

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DOCUMENTATIONS Apache Maven

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Some links

•  The main web site : » http://maven.apache.org

•  Project’s team wiki : » http://docs.codehaus.org/display/MAVEN

•  Project’s users wiki : » http://docs.codehaus.org/display/MAVENUSER

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Books

•  Nicolas De loof Arnaud Héritier » Published by Pearson » Collection Référence » Based on our own

experiences with Maven.

» From beginners to experts.

» In French only

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Books

•  Sonatype / O’Reilly : » The Definitive Guide » http://

www.sonatype.com/books

» Free download » Available in several

languages

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Books

•  Apache Maven 2 Effective Implementation » Brett Porter, Maria

Odea Ching » https://

www.packtpub.com/apache-maven-2-effective-implementation/book

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Books

•  Exist Global » Better builds with

Maven » http://

www.maestrodev.com/better-build-maven

» Free download

125

SUPPORT Apache Maven

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Support

•  Mailing lists » http://maven.apache.org/mail-lists.html

•  IRC » irc.codehaus.org - #maven

•  Forums » http://www.developpez.net/ forum maven » In French

•  Dedicated support » Sonatype and many others companies

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QUESTIONS ? Apache Maven

128

Licence et copyrights

•  Photos and logos belong to their respective authors/owners

•  Various ideas are coming from the excellent presentation done by Matthew McCullough : » http://www.slideshare.net/matthewmccullough/

maven-30-at-oredev

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Licence et copyrights

•  Content under Creative Commons 3.0 » Attribution — You must attribute the work in the manner

specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).

» Noncommercial — You may not use this work for commercial purposes.

» Share Alike — If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one.

•  http://creativecommons.org/licenses/by-nc-sa/3.0/us/

Technology

Apache Maven - eXo TN presentation