When reinstalling eclipse and importing my project back that was cloned from gitHub into a newly formatted machine there was an error and my project does not compile, it gives me a nonsense error on the console. What I saw was that some libraries were not there, libraries that do not belong to my original project maybe eclipse libraries themselves.
Console error: This error does not make sense because before I format it works and there is nothing wrong with the class resource manager
Exception in thread "main" java.lang.IllegalArgumentException: input == null!
at javax.imageio.ImageIO.read(Unknown Source)
at br.sp.mogi.imperiocongelados.res.ResourceManager.initialize(ResourceManager.java:142)
at br.sp.mogi.imperiocongelados.Principal.main(Principal.java:16)
Red exclamation mark next to project name
Buildpathwiththe6librariesheaccusesaremissing 
If I delete the missing libraries it compiles again, however I do not think it would be the most appropriate solution to delete libraries that I do not even know what they are for.