Anyone know the keyboard shortcut to copy/paste a line into a new line in Eclipse, without having to highlight the entire line?
ctrl-alt-down turns my whole screen upside down (I'm on windows). Interestingly, that's what's specified in the windows->preferences.
(Tested on Windows) [Per below comments, works as well in Ubuntu, IBM RTC 4 / RSA 9]
Copy LinesSelect AllOKFrom now on, for any line you want to duplicate, just press Ctrl+Shift+V.
You have to turn off the graphics hot keys that flip the screen. If you're on Windows, you need to right click on the Windows desktop and select "Graphics Properties..." (or something similar depending on your version of Windows). This will bring up a screen where you can manage graphics and display options, look for a place where you can disable hot keys, sometimes it's hidden under something like "Options and Support". Turn off the CTRL + ALT + ↑ and CTRL + ALT + ↓ hotkeys (alternatively you can just disable all graphics hot keys if you're not using them).
The advantage over Ctrl-Alt-Down followed by Ctrl-X suggested by other users is that it doesn't make eclipse think that the file was changed in any way. It's also faster and causes no problems even if the user has rotating screen issue with Ctrl-Alt-Down/Up keyboard shorcut. So there's no need to remap shorcuts for this.
Another way to go would be hitting Alt-Shift-Up until the entire line gets selected. If you've gone too far, of course you can select less with Alt-Shift-Down.
I've written the linecopypaste plugin for Eclipse that mimics Visual Studio's copy/cut/paste behaviour. I've also found copycutcurrentline which appears to do the same.
On Mac, I've tried the linecopypaste and it works great cmd+c -> Copy current (unselected) line, just like "yy" command in Vi/Vim cmd+v -> Paste it, like "p" command in Vi/Vim
Thank's Larsch for your work!
PD: Using Eclipse Luna 4.4.2 in Yosemite
Disabling the hot keys for the Intel Driver worked for me for Windows 7. However, for Windows 8, when I tried that, it prevented eclipse from getting the Ctrl-Alt-Down keystoke. I had to change the Intel driver key binding to Ctrl-Alt-F10 (or something else it will accept). Eclipse then gets the Ctrl-Alt-Down and copies the line.
We can assign any command to any action(given) in Eclipse
From Menu Bar go to Window > Preferences
then search for the keys
then search copy line
then click on copy line and then click on command in Binding
and peform a command which you wish to use for duplicating line i use ctrl+shift+d
you can choose whatever you want 
I am using Windows 7. To disable that all I did is to Right click on the Windows desktop and select "Graphics Properties" ->Options. Then selected "Off" at the left side on the resulting screen. This disabled all hotkey combination. I think there is no way to disable only some them, its all or none. Anyway I didn't need them. So now crtl+Alt+Up and Crtl+Alt+down works for me in Eclipse and my screen stays same :) I think similar option also exist in other versions of Windows. Have fun :)
The Ctrl+Alt+Down / Ctrl+Alt+Up flips my screen so I overrode that in the Eclipse shortcuts via Window => Preferences => General => Keys. Search for "dupl" to find the Duplicate Lines command. I overrode the default and chose Ctrl+Shift+D. For me, that's easy to remember just like Ctrl+D to delete lines
ctrl+alt+down/up/left/right takes precedence over eclipse settings as hot keys. As an alternative, I try different approach.
Step 1: Triple click the line you want to copy & press `Ctrl`-`C`(This will
select & copy that entire line along with the `new line`).
Step 2: Put your cursor at the starting of the line where you want to to paste
your copied line & press `Ctrl`-`V`.(This will paste that entire line & will
push previous existing line to the new line, which we wanted in the first place).
