1 public class Test {
2 private static Map<String,String> student;
3
4 private static void init() {
5 student = new LinkedHashMap<String,String>();
6 student.put("16010001", "tom");
7 student.put("16010002", "tony");
8 student.put("16010003", "j");
9 student.put("16010004", "yy");
10 }
11
12 public static void main(String[] args) {
13 init();
14 String key = null;
15 Scanner stdin = new Scanner(System.in);
16 System.out.println("Choose a SchoolId:");
17 for(Map.Entry<String, String> stu:student.entrySet()) {
18 System.out.println(stu.getKey()+"\t" + stu.getValue());
19 }
20 while(key == null) {
21 key = stdin.nextLine();
22 if (student.get(key) == null) {
23 System.out.println("Invalid choice!");
24 key = null;
25 }
26 }
27
28 System.out.println("Success!");
29 }
30 }
