Q:

How can I scroll left and right in Eclipse editor with the keyboard without moving the cursor?

To scroll within the Eclipse editor without moving the cursor up and down one can use CTRL+Down or CTRL+Up. But what about left and right?

A:

It is not possible. If you search keys in Eclipse's Preferences, you will find out that you only have Scroll up and Scroll down that you can set hotkeys on.
My recommendation would be changing the maximum line length in the editor. 
Make your code shorter. After all, looooong lines of code are not so readable. 
Also, resize your editor area. If you feel strangled, remove the Outline, TaskList, and Build view from your right side of Eclipse, and enlarge the editor.

