Fui criar o Java Project e além dos arquivos da biblioteca não aparecerem surgiram na aba de problemas 2 erros. Erros:
Description Resource Path Location Type
The project cannot be built until build path errors are resolved sintaxe-basica Unknown Java ProblemDescription Resource Path Location Type
Unbound classpath container: 'JRE System Library [JavaSE-9]' in project 'sintaxe-basica' sintaxe-basica Build path Build Path Problem