Downloading Eclipse plug-in update sites for offline installation

You can mirror p2 sites using Ant tasks:

<target name="springide">
    <echo>springide</echo> 
    <p2.mirror verbose="true">
        <repository location="${REPO_HOME}/springide" name="springide" append="true"/>
        <source>
            <repository location="http://springide.org/updatesite" />
        </source>
        <iu id="Core / Spring IDE" version="" />
        <iu id="Extensions / Spring IDE" version="" />
        <iu id="Integrations / Spring IDE" version="" />
        <iu id="Resources / Spring IDE" version="" />
    </p2.mirror>
</target>

or findbugs:

<target name="findbugs">

<echo>findbugs</echo>
    <p2.mirror verbose="true">
        <repository location="${REPO_HOME}/findbugs" name="findbugs" append="true"/>
        <source>
            <repository location="http://findbugs.cs.umd.edu/eclipse/" />
        </source>
        <iu id="edu.umd.cs.findbugs.plugin.eclipse.feature.group" version="" />
    </p2.mirror>
</target>

In order for this to work you have to run ant tasks in the same JVM as eclipse.

You can find IU ID:s by opening "Software Updates" and copy it from there. In Eclipse 3.5 there should be a More... button, in 3.4 you have to click on properties button.

Eclipse offers a way of mirroring these sites automatically, either through the command line or through ant tasks.

Mirror based on p2 information

$eclipse_home/eclipse -application org.eclipse.equinox.p2.artifact.repository.mirrorApplication -source $1 -destination $2
$eclipse_home/eclipse -application org.eclipse.equinox.p2.metadata.repository.mirrorApplication -source $1 -destination $2

Reference: Equinox p2 repository mirroring

Mirror based on site.xml information

java -jar $eclipse_home/plugins/org.eclipse.equinox.launcher_*.jar -application org.eclipse.update.core.standaloneUpdate -command mirror -from $from -to $to

Reference: Running the update manager from the command line

You can follow the evolution of these scripts in my script repository.

Most Eclipse plug-ins can be installed without the Eclipse updater, by copying the required JARs available at the update site, into the plugins and features directories of the Eclipse installation.

In certain cases, it is necessary to start Eclipse with a -clean switch.

Here's an example of how to do this for the m2eclipse plugin:

1. The m2eclipse update site is http://m2eclipse.sonatype.org/update. Identifying the list of JARs required is the first step. This is normally found in the site.xml file; in this case, you'll find it in http://m2eclipse.sonatype.org/update/site.xml.
2. Filter the list of JARs to be downloaded to the version of the plugin that you intend to use. This can be determined by the version attribute for each "feature". If you are lucky, you'll find the description of the JAR in the category node.
3. Note the url attribute of each JAR that needs to be downloaded. This will include the subdirectory on the server where the JAR is available, and also the directory in the Eclipse installation where they need to be placed.

PS: This method is a bit hackish, but it is based off the site-map reference. But do refer to the update

Update

I haven't attempted this, but you can create a local mirror site, from where everyone else can pickup the Eclipse plug-ins. In Galileo, this can be done by running the Eclipse updater in the standalone mode via the mirror command.

After struggling with mirroring for some time, I realized that it is much easier (at least, for me) to use "wget" instead.

In short:

1. Download the site:

   wget --recursive --no-parent http://url.of/updatesite

2. Take the content of the downloaded update site and move it to your offline environment

3. Add your offline update site directory to the list of available software sites via "Local..." button.

You can read about it with more details here.