1.普通集合創建
// 普通Collection的創建
List<String> list = Lists.newArrayList();
Set<String> set = Sets.newHashSet();
Map<String, String> map = Maps.newHashMap();
2.針對Map<String,List<String>>結構添加數據的技巧
以往的寫法
Map<String,List<Integer>> map = new HashMap<String,List<Integer>>();
List<Integer> list = new ArrayList<Integer>();
list.add(1);
list.add(2);
map.put("aa", list);
System.out.println(map.get("aa"));//[1, 2]
現在
Multimap<String,Integer> map = ArrayListMultimap.create();
map.put("aa", 1);
map.put("aa", 2);
System.out.println(map.get("aa")); //[1, 2]