数组转List
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
List staffsList = Arrays.asList(staffs);12需要注意的是，
Arrays.asList()返回一个受指定数组决定的固定大小的列表。所以不能做add、remove等操作，否则会报错。List staffsList = Arrays.asList(staffs); staffsList.add("Mary"); // UnsupportedOperationExceptionstaffsList.remove(0); // UnsupportedOperationException1
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如果想再做增删操作呢？将数组中的元素一个一个添加到列表，这样列表的长度就不固定了，可以进行增删操作。
List staffsList = new ArrayList<String>();for(String temp: staffs){ staffsList.add(temp); } staffsList.add("Mary"); // okstaffsList.remove(0); // ok1
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数组转Set
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
Set<String> staffsSet = new HashSet<>(Arrays.asList(staffs));
staffsSet.add("Mary"); // okstaffsSet.remove("Tom"); // ok1234List转数组
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
List staffsList = Arrays.asList(staffs);
Object[] result = staffsList.toArray();1234List转Set
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
List staffsList = Arrays.asList(staffs);
Set result = new HashSet(staffsList);1234Set转数组
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
Set<String> staffsSet = new HashSet<>(Arrays.asList(staffs));
Object[] result = staffsSet.toArray();1234Set转List
String[] staffs = new String[]{"Tom", "Bob", "Jane"};
Set<String> staffsSet = new HashSet<>(Arrays.asList(staffs));
List<String> result = new ArrayList<>(staffsSet);