How to change eclipse font sizes
Try this:
Edit e4_default_gtk.css.
vim ECLIPSE_HOME/plugins/org.eclipse.ui.themes_*/css/e4_default_gtk.css
Add at the end:
* {
font-size:8;
}
Save and start Eclipse.
This worked for me on Ubuntu 14.04 and Eclipse Luna.
I figured out the missing pieces of this. The hard part is controlling the font size for the non-editor views, like the package explorer. I discovered the following, which did the trick for me:
Smaller font sizes for Eclipse on Linux