A selection plugin can be applied to both an XML document and a non-XML document. It works as follows: the user makes a selection in the editor, displays the contextual menu, and selects from the Plugins submenu the item corresponding to the plugin.
This plugin type allows the developer to work with a custom designed protocol for retrieving and storing files. It can lock a resource on opening it in Oxygen XML Developer. This type of plugin extends the custom protocol plugin type with resource locking support.