How do I add an action to a the popup menu of the Java editor?

The simplest way is to run New Action Wizard (File > New... > Module Development > Action) which creates an action for you and registers it in your layer.xml.

1. On the first tab, choose Conditionally Enabled action and select EditorCookie as the cookie class.
2. On the second tab, check Editor Context Menu Item and choose MIME type (text/x-java in this case) and position.

You can also declare your action in your layer manually:

<folder name="Editors">
  <folder name="text">
    <folder name="x-java">
      <folder name="Popup">
        <file name="org-mymodule-MyAction.instance"/>
      </folder>
    </folder>
  </folder>
</folder>

You can also use Editors/Popup/ to add an action to all editor kits.

See also:

• How do I add an action to a file of a given mime-type?
• How do I add an action to a folder?
• How do I add an action to the text-editor popup menu?
• How do I add an action to the NetBeans menu bar?
• How do I add an action to the NetBeans tool bar?
• How do I add an action to my custom node?