Step 3. Import the Processing libraries

Eclipse doesn't know anything about Processing so we'll have to go and get the Processing libraries ourselves. One way to do this is by pointing Eclipse to Processing's "core library" directory, however, it's sometimes a good idea to copy the necessary Processing files into the project folder itself so that everything stays together. Go to:

FILE --> IMPORT --> GENERAL --> FILE SYSTEM.

Click next. Click browse and find the Processing application. On Windows you will then want to look inside the directory called "lib", but on Mac (for Processing 2.0) you'll have to go inside the application's "package contents": Processing->Contents->Resources->Java. Select the file "core.jar" inside the "library" folder.