Maven: How to install a plugin in offline mode

Question

I'm sitting behind a firewall and therefore maven can't connect to central repositories (error message is given below).

However, I can connect to the internet via HTTP.

How can I install a maven plugin (e. g. archetype) in offline mode (i. e. download some file in a browser and then install the plugin by executing some commands) ?

Thanks in advance

Dmitri

P. S.: Here is the error message:

E:\>mvn archetype:generate -DarchetypeGroupId=com.vaadin
 -DarchetypeArtifactId=vaadin-archetype-clean -DarchetypeVersion=LATEST -DgroupI
d=at.swdev -DartifactId=pcc -Dversion=1.0 -Dpackaging=war
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'archetype'.
[INFO] org.apache.maven.plugins: checking for updates from central
[WARNING] repository metadata for: 'org.apache.maven.plugins' could not be retri
eved from repository: central due to an error: Error transferring file: Connecti
on refused: connect
[INFO] Repository 'central' will be blacklisted
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] The plugin 'org.apache.maven.plugins:maven-archetype-plugin' does not exi
st or no valid version could be found
[INFO] ------------------------------------------------------------------------
[INFO] For more information, run Maven with the -e switch
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1 second
[INFO] Finished at: Thu Jul 22 15:17:00 CEST 2010
[INFO] Final Memory: 1M/15M
[INFO] ------------------------------------------------------------------------

Answer 1

I'm sitting behind a firewall and therefore maven can't connect to central repositories (error message is given below). However, I can connect to the Internet via HTTP.

Maybe you should clarify a bit because Maven uses HTTP as well. If you connect through some kind of proxy, you CAN configure Maven to do so by declaring the proxy in your ~/.m2/settings.xml. See Configuring a proxy.

How can I install a maven plugin (e. g. archetype) in offline mode (i. e. download some file in a browser and then install the plugin by executing some commands)?

You can install any jar in your local repository using the install:install-file goal (see the Usage page). But this is only a small part of the story, you'll need to install dependencies of the plugin too. And then dependencies of dependencies. This will very quickly become a real nightmare and unmanageable task (that Maven precisely tries to solve). So either:

• Configure Maven to access Internet if this is possible ~or~
• Setup a corporate repository (like Nexus) on a dedicated machine, see with your admins how to allow it to access Internet) and configure your Maven client to use it ~or~
• Copy a "pre-populated" local repository from an existing machine to your machine and run maven offline (with all the limitations this implies) ~or~
• Don't use Maven