Removing Blank Lines in Eclipse

Many times I end up using source files from somebody else. And such files might have a lot of empty lines in it I want to get removed. The question is: how to get rid of empty or blank lines in the Eclipse Editor view? Or even better: how to merge multiple empty lines into one?

Shortcut: CTRL+D

Deleting a line is easy: I place the cursor on a line and press CTRL+D (for line Delete). That works as well for multiple line selection. Using the ‘Mother of all shortcuts‘ reveals even more shortcut options:

Delete Commands

This approach is fine, but manual. There must be something better.

Search-And-Replace: Regular Expression

And there is: To automatically remove empty lines, the Search-And-Replace functionality helps. For this I press CTRL-F (for Find) and configure it like this:

Regular Expression to Remove Empty Lines

The magic is using a regular expression checkbox. It uses the regular expression

^\s*\n

to find one or multiple empty lines and replaces it with ‘nothing’. That way I can clean up a full file and get rid of all empty lines.

If I do not remember the syntax of regular expressions any more, then there is help too: the dialog has content assist available:

Content Assist

So that way pressing CTRL+SPACE helps a lot:

Content Assist Help

Merging Empty Lines

With this in mind, it is easy to do something more advanced : To merge multiple empty lines into a single one. Again, a regular expression does the magic work:

Merging multiple empty lines into a single one

With this, the regular expression

^\s*\n

finds one or multiple empty lines (as before), and it replaces it with a single empty line:

\R

Now the sources need much less screen real estate .

Happy removing:-)