sample.properties
pref1.pref2.abc.suf = 1
pref1.pref2.def.suf = 2
...
...

@ConfiguraionProperties
@PropertySource(value = "classpath:sample.properties")
public class Config{
    @Autowired
    private Environment env;

    public HashMap<String, Integer> getAllProps(){
        //TO-DO
    }
}