Types of maven repository,Comparison of various maven repository managers

Maven is reducing the duplication of dependent software libraries (jars) required to build an application. As of now we have finished local setup, now will move to maven repository manager setup.

Repository is storing all the software libraries in a remote store. Libraries private to the organization cannot be uploaded. By setting up an internal maven repository, an organization can avail of the benefits of a maven repository.

Repository jars has been used by maven pom.xml files.

Types of maven repository

1. Local repository - exists on developer's machine and is maintained by the developer. It is in sync with the maven repositories defined in the 'settings.xml' in their '~home/.m2' folder. If no private remote internal repository is setup and listed in the pom.xml file or settings.xml file, then this local repository on developer's machine is synchronized with the public maven repository at ibiblio.org.

2. Private remote internal repository - This repository which we will setup. We will change the maven pom.xml or settings.xml to use this repository

3. Public remote external repository - This is the public external repository at ibiblio.org. By default, maven synchronizes with this repository.

Comparison of various maven repository managers

Some of the popular open source and free maven repositories are:

Standard maven proxy from codehaus - http://maven-proxy.codehaus.org/
Dead simple Maven Proxy(DSMP) - http://www.pdark.de/dsmp/
Proximity - http://proximity.abstracthorizon.org/. Now it is Nexus
Artifactory - http://www.jfrog.org/sites/artifactory/latest/

	Standard maven repository	Dead simple Maven Proxy (DSMP)	Proximity	Artifactory
Admin tools	No	Basic	Yes	Yes
Repository browser	Basic	No	Yes	Yes
Deployable in standard web server (e.g. Tomcat or Jetty)	Yes, but not configurable	No	Yes	Yes(works in Tomcat and bundled with Jetty)
Create, edit and delete sub repositories	Yes	Yes	Yes	Yes
Bulk import/export artifacts	No	No	No	Yes
Easy to setup and use	Yes	No, build from source	Yes	Yes(Ajax web UI)
Backup facility	No	No	No	Yes(using Java quartz API and 'cron' expressions)
Issue tracker, forums and other sources of information	Jira, IRC	No	Wiki and issues tracker	Jira issue tracker. Good documentation on site

Anyone who was using Proximity is now encouraged to use Nexus (http://www.sonatype.org/nexus/). The entire codebase of Proximity was absorbed into Nexus and Nexus provides a migration path for all Proximity users.

Comparison of various maven repository managers

Nexus uses file system to store artifacts and metadata, where as Artifactory uses Derby DB by default. Artifactory can also be configured to use a handful of RDMBS for artifact storage (MySQL, PostgreSQL, Oracle...) as well as using the file system. Artifactory takes the polar opposite approach and stores the metadata and the artifacts themselves in a huge database. The reason they claim it's needed is for transactional behavior. Using a database doesn't guarantee transactional and it certainly isn't the only way to get transactional behavior.

Nexus jar weighs about ~13M while Artifactory is about ~37M. Artifactory memory consumption is about 50% higher than Nexus.
For maven build, had to edit maven settings.xml to use Nexus as releases and plugins repository, and built my project using mvn install, after enabling remote indexing on Nexus. Artifactory has is the ability to generate and save a settings.xml file
Building the project using Artifactory took about 5 minutes whereas building using Nexus took about 8.5 minutes. Not exact science kind of faster, but still good for initial impression.