How to give the static value to HashMap?
问题 I have HashMap like: static HashMap<String,ArrayList<Media>> mediaListWithCategory=new HashMap<String,ArrayList<Media>>(); I have value like: January: -Sunday -Monday Februsry: -Saturday -Sunday -Thursday March: -Monday -Tuesday -Wednesday How can I statically assign these values when defining the hash map? 回答1: You can populate it in a static block: static { map.put("January", Arrays.asList(new Media("Sunday"), new Media("Monday"))); } (You should prefer interface to concrete classes. define