1、数组转List
String[] arr = new String[]{"A", "B", "C"}; List list = Arrays.asList(arr); //返回固定大小,不能做add和remove等操作
2、数组转Set
String[] arr= new String[]{"A", "B", "C"}; Set<String> set= new HashSet<>(Arrays.asList(arr)); //可以直接对set进行add和remove操作
3、List转数组
String[] arr= new String[]{"A", "B", "C"}; List list = Arrays.asList(arr); Object[] result = list.toArray(); //使用toArray()方法
4、List转Set
String[] arr= new String[]{"A", "B", "C"}; List list = Arrays.asList(arr); Set result = new HashSet(list); //list转set
5、Set转数组
String[] arr= new String[]{"A", "B", "C"}; Set<String> set= new HashSet<>(Arrays.asList(arr)); Object[] result = set.toArray(); //使用toArray()方法
6、Set转List
String[] arr= new String[]{"A", "B", "C"}; Set<String> set= new HashSet(Arrays.asList(arr)); List<String> result = new ArrayList<>(set);