Selecting Maven projects to import used to take an inordinate amount of time, due to a suboptimal - I love that word :-) - Maven Lifecycle Mapping Analysis (LMA). LMA is used to determine whether the projects would require further configuration to operate properly in Eclipse. That LMA is now only run after projects are imported, making selection of projects to import much, much faster (< couple seconds vs 1-2 min for the wildfly 8.0 codebase and its 130 projects, for instance)

After import, lifecycle mapping error markers are collected on imported projects and the discovery service is invoked to find proposals to fix those errors.

Another improvement to this workflow is the ability to easily import multi-module projects to an Eclipse Working Set. The default name is inferred from the root project but can be overridden manually:

More performance improvements during import itself are to be expected to be included in m2e 1.6.0.

See bugs 409732, 408042 and 417466.

Maven project instance caching strategy has been revisited to reduce memory consumption. For a workspace with 300+ projects for instance, heap memory used went from 2.5GB down to well under 1GB without any noticeable side effects.

See Igor’s announcement and bug 410954.

Before m2e 1.5, by default, Nexus indexes were downloaded on new workspace startup, then subsequently once a week. Depending on your internet connection, that whole process could take 15 minutes or more, heavily pegging the CPU. Once the indexes were updated, the size of the workspace would increase by approximately 500 MB. Even though space is relatively cheap these days, those with many workspaces (eg., for testing) or large workspaces, this extra disk usage can add up quickly.

m2e 1.5.0 now has this feature disabled by default. You can still enable it in Preferences  Maven  Download repository index updates on startup. One major downside of having this feature disabled by default though, is Archetype and Artifact/Plugin searches are now much less efficient, as they rely on this indexed content.

See bug 404417

The JBoss Tools team contributed its Maven Profile management interface to m2e 1.5.0. This new interface eases switching between profiles.

Rather than right-clicking on a project, going to the Properties  Maven page, then manually (mis)typing a list of active or disabled profiles, you can now just use Ctrl+Alt+P to open the new Maven Profile selection interface.

The new interface is also accessible from the Maven context menu: Right-click project Maven  Select Maven Profiles…​

The list of available profiles is inferred from profiles defined in:

When several projects are selected, only the common available profiles are displayed for selection. Common profiles are profiles defined in settings.xml or profiles having the same id in different pom.xml.

You can learn more about that feature from the original JBoss Tools blog

See bug 428094

The Update Maven Project dialog (launched via Right-click project Maven  Update Project…​ or via Alt-F5), now shows a dirty overlay on projects which need updating.

Additionally, an "Add out-of-date" button adds all out-of-date (OOD) projects to the current selection. If an OOD project has not been selected, a warning is shown underneath the selection table with a link equivalent to "Add out-of-date". Warning text and "Add out-of-date" button tooltip show a count of unselected OOD projects.

See it in action: http://screencast.com/t/27S0qeca

See bug 422667

There’s a very popular question on StackOverflow about an m2e bug that plagued many users of the maven-eclipse-plugin: m2e would throw Unsupported IClasspathEntry kind=4 exceptions on classpath entries generated by the maven-eclipse-plugin (one of the reasons why you should never mix maven-eclipse-plugin and m2e).

m2e 1.5.0 no longer complains about these unsupported classpath entries, but unexpected classpath issues may still arise, should you mix duplicate jars from m2e and those added by the maven-dependency-plugin.

See bug https://bugs.eclipse.org/394042

Ever connected to a network with limited Internet access or simply stayed at a hotel where you needed to get past a for-pay-firewall, resulting in HTML pages being downloaded instead of jars? There’s nothing better to pollute your local Maven repository. Maven CLI builds can use these flags:

m2e now has a global Checksum Policy available in Preferences  Maven, that will help you keep your sanity, and yor local repository clean:

While m2e actually won’t create any Warning markers on projects when "Warn" is selected, it will override existing checksum policies set on repositories.

See bug https://bugs.eclipse.org/418674

m2e has been known for generating specific errors that have puzzled more than one user in the past:

With the new Preferences  Errors/Warnings page, users can now decide according to their own needs whether these errors should be downgraded to Warning, or even be ignored entirely.

See bugs 433776, 434053

A few changes have been made with regards to the Maven runtime(s):

See bugs 427932, 418263, 432436

In order to lower the contribution barrier and increase contributor diversity, the m2e project now accepts changes contributed via the Gerrit review system. Head over the wiki that explains how to use it. Does it work? Hell yeah! After several significant contributions, Anton Tanasenko has joined the m2e team as commiter!

Welcome Anton!

See bug 374665

With new blood on the m2e team, numerous fixed bugs and some big new features & improvements, m2e 1.5.0 is a pretty exciting release. Hope you guys appreciate this year’s release, before an even better version next time.

So if you haven’t installed m2e 1.5.0 yet, head over to https://www.eclipse.org/m2e/download/ and have at it.

We’d love to hear your feedback on the mailing list, or whether you report bugs or enhancement requests.

Fred Bricon
@fbricon