Question

if (name[name.length - 1 - 1] == null) 是什么意思？？？

System.out.println("欢迎使用迷你DVD管理器");
System.out.println("----------------------------");
System.out.println("1.新增DVD");

System.out.println("----------------------------");
System.out.print("请选择:");
select = input.nextInt();
switch (select) {
case 1:
System.out.println("---新增DVD");
System.out.print("请输入新增DVD的名字：");
String named = input.next();
if (name[name.length - 1 - 1] == null) {
for (int i = 0; i < name.length - 1; i++) {
if (named.equals(name[i])) {
System.out.println("新增的" + named + "已存在！");
break;

Answer 1

name[name.length - 1 - 1]应该是确定里面是否有值，name.length如果小于等于1，那就是说name[name.length - 1 - 1]的下标小于0