NOTE:
The mentioned LATEST and RELEASE metaversions have been dropped for plugin dependencies in Maven 3 "for the sake of reproducible builds", over 6 years ago.
(They still work perfectly fine for regular dependencies.)
For plugin dependencies please refer to this Maven 3 compliant solution.
If you always want to use the newest version, Maven has two keywords you can use as an alternative to version ranges. You should use these options with care as you are no longer in control of the plugins/dependencies you are using.
When you depend on a plugin or a dependency, you can use the a version value of LATEST or RELEASE. LATEST refers to the latest released or snapshot version of a particular artifact, the most recently deployed artifact in a particular repository. RELEASE refers to the last non-snapshot release in the repository. In general, it is not a best practice to design software which depends on a non-specific version of an artifact. If you are developing software, you might want to use RELEASE or LATEST as a convenience so that you don't have to update version numbers when a new release of a third-party library is released. When you release software, you should always make sure that your project depends on specific versions to reduce the chances of your build or your project being affected by a software release not under your control. Use LATEST and RELEASE with caution, if at all.
See the POM Syntax section of the Maven book for more details. Or see this doc on Dependency Version Ranges, where:
- A square bracket (
[ & ] ) means "closed" (inclusive).
- A parenthesis (
( & ) ) means "open" (exclusive).
Here's an example illustrating the various options. In the Maven repository, com.foo:my-foo has the following metadata:
<?xml version="1.0" encoding="UTF-8"?><metadata>
<groupId>com.foo</groupId>
<artifactId>my-foo</artifactId>
<version>2.0.0</version>
<versioning>
<release>1.1.1</release>
<versions>
<version>1.0</version>
<version>1.0.1</version>
<version>1.1</version>
<version>1.1.1</version>
<version>2.0.0</version>
</versions>
<lastUpdated>20090722140000</lastUpdated>
</versioning>
</metadata>
If a dependency on that artifact is required, you have the following options (other version ranges can be specified of course, just showing the relevant ones here):
Declare an exact version (will always resolve to 1.0.1):
<version>[1.0.1]</version>
Declare an explicit version (will always resolve to 1.0.1 unless a collision occurs, when Maven will select a matching version):
<version>1.0.1</version>
Declare a version range for all 1.x (will currently resolve to 1.1.1):
<version>[1.0.0,2.0.0)</version>
Declare an open-ended version range (will resolve to 2.0.0):
<version>[1.0.0,)</version>
Declare the version as LATEST (will resolve to 2.0.0) (removed from maven 3.x)
<version>LATEST</version>
Declare the version as RELEASE (will resolve to 1.1.1) (removed from maven 3.x):
<version>RELEASE</version>
Note that by default your own deployments will update the "latest" entry in the Maven metadata, but to update the "release" entry, you need to activate the "release-profile" from the Maven super POM. You can do this with either "-Prelease-profile" or "-DperformRelease=true"
It's worth emphasising that any approach that allows Maven to pick the dependency versions (LATEST, RELEASE, and version ranges) can leave you open to build time issues, as later versions can have different behaviour (for example the dependency plugin has previously switched a default value from true to false, with confusing results).
It is therefore generally a good idea to define exact versions in releases. As Tim's answer points out, the maven-versions-plugin is a handy tool for updating dependency versions, particularly the versions:use-latest-versions and versions:use-latest-releases goals.
Best Answer
I'm sure that if you only talk about storing binaries from "
mvn deploy" both will do fine.We use Artifactory very extensively with all upgrades along the way. Lots of projects, numerous snapshots deployed and external repos proxied. Not a single problem. I find it hard to explain how other people experience issues with its DB, indexing or anything else. Nothing like that ever happened to us. Also, Artifactory allows to store data on a disk and only use a DB for storing metadata, it is quite flexible (see more here).
What makes those applications very different is their approach towards integration with other build tools and technologies.
Nexus and Sonatype are pretty much locked on Maven and m2eclipse. They ignore anything else and only recently started to work on their own proprietary Hudson integration (see their Maven 3 webinar).EDIT: This is not true anymore as of 2017 Nexus gives a much larger support for other build tools End of EditArtifactory provides an awesome Hudson, TeamCity and Bamboo integration, and Gradle / Ivy support. So while Nexus gives you nothing once you step out of Sonatype "comfort zone" (Maven, m2eclipse), Artifactory embraces and collaborates with all major build tools.
In fact, being able to deploy build artifacts from Hudson, when job has finished, and not by "
mvn deploy" is a huge difference: Artifactory Hudson plugin makes an atomic-like deploy of all artifacts at once, only when a build job finished successfully. "mvn deploy" runs after each module and can deploy a partial set of artifacts if a build job fails in the middle. Deploying from Maven on module completion and not from a build server on job completion is really a bad thing to do.As you see, Artifactory thinks "outside the box" while Nexus thinks "inside the box" and only cares about Maven and Maven artifacts.
Something else that makes Artifactory more accessible is their cloud-based Artifactory Online solution. For about $80 a month you have your own Artifactory instance, no need to dedicate any server for it.
Artifactory has a simple and straightforward REST API, don't know how it works for Nexus. Edit Nexus has also a REST API that you can use easily as well.
To summarize, for basic storage of Maven artifacts I think both are fine.
But while Nexus stops there being strictly a "Maven repository manager", Artifactory goes on and on, being a general "Binaries storage" for binaries of any kind, from any build tool and CI server.