# Installing and Using Plugins

A plugin is an application which is loaded and runs as part of another, host application. Plugins respond to user commands and perform tasks that supplement the host application's features.

This chapter covers installing, updating and removing plugins. Documentation for the plugins themselves can be found in Help>jEdit Help, and information about writing plugins can be found in .

## The Plugin Manager

Plugins>Plugin Manager displays the plugin manager window. It consists of three tabs: Manage, Update and Install. The Manage tab lists all installed plugins; clicking on a plugin in the list will display information about it.

To remove plugins, select them (multiple plugins can be selected by holding down Control) and click Remove. This will display a confirmation dialog box first.

To view plugin documentation, select a plugin and click Help. Note that plugin documentation can also be accessed by invoking Help>jEdit Help.

After you have tuned jEdit to your liking and want to install the same set of plugins onto another host, or another user's profile, you can export your currently installed plugin list as an xml file, known as a PluginSet. The Save rollover button allows you to save the list of installed and loaded plugins to an XML file. See for more information.

Plugins>Plugin Options displays a dialog box for changing plugin settings.

## Installing and Updating Plugins

Plugins can be installed in two ways; manually, and from the plugin manager. In most cases, plugins should be installed from the plugin manager. It is easier and more convenient.

To install plugins manually, go to http://plugins.jedit.org in a web browser and follow the directions on that page.

To install plugins from the plugin manager, make sure you are connected to the Internet and click the Install tab in the plugin manager window. The plugin manager will then download information about available plugins from the jEdit web site, and present a list of plugins compatible with your jEdit release.

Click on a plugin in the list to see some information about it. To select plugins for installation, click the check box next to their names in the list.

The Total size field shows the total size of all plugins chosen for installation, along with any plugins that will be automatically downloaded in order to fulfill dependencies.

If a previously saved PluginSet was selected, it will automatically be loaded whenever the Install tab is created, and you will see the filename in the hovertip of the choose rolloverbutton, as well as all of the plugins in that set already checked for you.

You can clear the active PluginSet with the clear button next to it, or choose a different PluginSet xml file with the choose button. See for more information.

Once you have specified plugins to install, click Install to begin the download process.

By default, the plugin manager does not download plugin source code, and installs the downloaded plugins in the `jars` subdirectory of the user-specific settings directory. These settings can be changed in Plugin Manager pane of the Utilities>Global Options dialog box; see .

The Update tab of the plugin manager is very similar to the Install tab. It lists plugins for which updated versions are available. It will also offer to delete any obsolete plugins.

Proxy Servers and Firewalls

If you are connected to the Internet through an HTTP proxy or SOCKS firewall, you will need to specify the relevant details in the Proxy Servers pane of the Utilities>Global Options dialog box; see .

## Plugin Sets

A PluginSet is a collection of plugins, represented as an XML file. These XML files can be created from the save button of the Manage tab of the Plugin Manager. Saving a PluginSet remembers all of the currently loaded plugins.

When a PluginSet has been saved, it becomes the "default pluginset", which means that if you unload/uninstall plugins from that set and go back to the Install tab, you should see them selected for download again. To clear this setting, click on the clear button in the Install tab.

It is posisble to Choose/Open a PluginSet from the Manage or the Install tab. The behavior of choosing a PluginSet depends on which tab you are on when you choose it. From the Manage tab, it unloads plugins that are loaded but not in the list. From the Install tab, it selects plugins from that list that are not loaded, marking them for download from Plugin Central.

When choosing a PluginSet, the path can be given as a remote URL. This helps teachers and sysadmins direct the students/slaves to a standard set of plugins that are required for the course/job.