How To Add jQuery Autocompletion in Eclipse

1. Help > Install New Software
2. Add Aptana download site (http://update.aptana.com/install/studio/)
3. Important – Uncheck “Group Items By Category”
4. Select Aptana Web Development Tools (Subset of entire studio)
5. Complete Installation
6. On Restart of Eclipse you get a “Customize Aptana Studio” popup
7. Under AJAX Libraries select JQuery
8. Get “Aptana Support for jQuery”
9. Complete installation (second restart of Eclipse)
10. Open a JS file, Window – Open Perspective – Other – Aptana
11. Still doesn’t work, so Window – Preferences – Aptana / Editors / JavaScript / Code Assist
12. Check JQuery
13. File Restart
14. File New Project – Aptana – Web Project
15. Create JS file and paste whatever you were working on here, or start new

source: StackOverflow