Ok, so this is probably a NooB question (I\'m more of a C++ guy), but I\'m lost in the java woods and its frameworks forests...
I\'m trying to look into eclipse RCP
Your comment indicates this is for Guava, so you want the JSR305 library, which extends the javax package.
javax
2020 Update: Note that this library breaks the Oracle licensing agreement and Guava has since moved to checkerframework's Nullable annotation.