Eclipse has support for doing spellcheck of words in code or comments.
The configuration is handled from Preferences -> General -> Editors -> Text Editors -> Spelling. (Note: This dialog has some display problem and renders a very long page. Scroll down slowly to be able to view all the items.)
In the Options, you can choose all the cases where spellcheck can be ignored.
In the Dictionaries section, you can choose the language dictionary to use (I use English (United States). You can also pick a text file to use when you add your own words to dictionary. (I like to point this to my Vim text spellfile.) You can also choose the Encoding (I pick UTF-8).
Misspelt words appear in the editor underlined with a red squiggle. Right-click to fix the misspelling or add the word to your dictionary.
Tried with: Eclipse 4.5 and Ubuntu 14.04