Apache Maven

Apache Maven is one of Apache's most successful projects, right there next to its HTTPD and Tomcat servers, Ant build system, and Cassandra and CouchDB databases.

Maven as a tool targets developers only and is a seamless development environment for Java programming that will automate various common operations encountered and carried out during the process of setting up, coding, and deploying a project.

Developers can automate project builds, render changelogs, keep separate codebases, run unit tests, get code coverage reports, manage dependencies, and even run mailing lists from a Maven installation.

A single Maven installation can be used to manage unlimited projects, and the project also benefits from a free JAR repository for automatically downloading and installing repositories automatically, just like Perl's famous CPAN and Node.js' npm repos.

All of this is handled via POM, the Project Object Model, and its famous pom.xml configuration files you find in almost all of today's Java-based projects. If you've seen it, then probably the project is managed using Maven.

What is new in this release:

• Switched access to Maven Central to HTTPS.

What is new in version 3.3.3:

• Switched access to Maven Central to HTTPS.

What is new in version 3.3.1:

• Switched access to Maven Central to HTTPS.

What is new in version 3.2.5:

• Switched access to Maven Central to HTTPS.

What is new in version 3.0.4:

• Some enhancements are now included by default:
• HTTP(S) connection pool.
• Default preemptive authentication support.
• A default read timeout configured to 30 minutes.

What is new in version 3.0.3:

• Allow hexadecimal parameters
• Display maven home in version info
• Simplify drop in of 3rd party extensions for Maven core
• API to calculate execution plan without full mojo execution configuration
• Allow to configure plugin parameters of type java.util.Properties just like a map
• Allow to configure array/collection type plugin parameters via system properties
• Allow to configure array-typed plugin parameters from expressions yielding collections and vice versa
• Allow to condense configuration of plugin parameter beans that commonly require only one value
• JAVA_HOME auto discovery
• Obey generics in plugin collection parameters when populating them
• Allow to inline collection/array items within plugin

What is new in version 2.2.1 / 3.0:

• Bug Fixes:
• Snapshot artifacts that could not be downloaded due to communication problems are "blacklisted" for a day by default.
• Snapshot version not resolved for version range
• NPE in dependency resolution code for TC plugin
• Ant-based mojo using maven-script-ant:2.1.0+ cause NPE
• Appassembler Maven Plugin doesn't work like as it should
• Difference in compile scope dependency resolution
• POM artifacts passed into MavenProjectBuilder.buildFromRepository() are no longer resolved
• Unable to obtain archiver for extension 'zip'
• 'org.apache.maven.plugins:maven-install-plugin:2.3.1'. A required class is missing: org.codehaus.plexus.digest.Digester
• Dependencies in forked reactor projects are not resolved when aggregator bound to lifecycle forks
• Conflict resolution does not pick sub tree of nearest dependency if farther conflicting dependency has wider scope
• Maven cannot build if loaded in a classloader that is not backed by a real JAR file / classpath
• Custom Maven Plugin regression in Maven 3.x, custom ComponentConfigurator causes infinite loop
• Eary dependency resolution attempts for reactor projects prevent their later resolution from the reactor
• NPE in legacy.DefaultWagonManager.getArtifact
• Checksum failures aren't logged
• Maven 3 Regression: Missing constructor of org.codehaus.plexus.component.configurator.converters.special.ClassRealmConverter
• MavenProject.getParent() ignores configured repositories
• Incorrect recursive expression cycle errors (update plexus-interpolation)
• Interpolation error due to cyclic expression for one of the POM coordinates gets needlessly repeated
• Repositories discovered in dependency POMs override repositories configured for original resolution request of POM
• MavenProject.getDependencyArtifact() returns artifacts without version for dependency with version range
• Improvements:
• Metadata for snapshots should include classifier
• Allow class realm manager delegates to alter public part of Maven core realm
• Maven Java API does not give nice error messages when improperly configured
• Multiple failures need additional whitespace
• Relative path errors could be more explicit
• New Features:
• Create a Maven API for component configuration

What is new in version 2.2.1:

• Bug fixes:
• MNG-3265 - maven-model Extension.equals causes NPE when any field is uninitialized
• MNG-3506 - Custom ArtifactHandler not resolved for project when an additional plugin with extensions is defined in parent pom
• MNG-3753 - ArtifactResolverDiagnoser.diagnose() fails with NPE if nested IOException has no detail message
• MNG-4189 - Maven not picking up specific timestamped version dependency when a later timestamped version was downloaded and already present in the local repository
• MNG-4218 - NPE in AbstractArtifactResolutionException if DefaultArtifactResolver.resolveTransitively is interrupted
• MNG-4228 - [regression] Authorization failed: Not authorized by proxy.
• MNG-4235 - [regression] Maven 2.2.0 produces invalid checksums during deployment to secured HTTP repo
• MNG-4236 - [regression] http wagon uploads files twice with Maven 2.2.0 when preemptive auth is disabled (default setting)
• MNG-4238 - Custom ArtifactHandler provided by build extension isn't used for project artifact
• MNG-4240 - Direct dependencies with scope == provided will not have their transitive dependencies resolved for compiling and testing
• MNG-4270 - ArtifactHandler, LifecycleMapping from plugin dependency is not used when plugin extensions are enabled
• MNG-4275 - [regression] Direct relocations no longer log at WARNING level : MNG-3380 conflicts with MNG-1689
• Improvements:
• MNG-4254 - Support selection of wagon implementation for a particular protocol
• MNG-4279 - wagon provider selection should fail gracefully and use protocol for roleHint if protocol-provider roleHint isn't available.

Requirements:

• Java 1.6 or higher
• Apache Ant 1.8 or higher