java内部类-局部内部类

 1 package face_09;
 2 /*
 3  * 内部类可以存放在局部位置上。
 4  *
 5  * 内部类在局部位置上只能访问局部中被final修饰的局部变量。
 6  */
 7 /*class Outer {
 8     int num = 3;
 9     void method() {
10
11         final int x = 9;
12         class Inner {
13             void show() {
14                 System.out.println("show..."+x);//从内部类中访问局部变量，需要把x声明为最终类型，final
15             }
16         }
17
18         Inner in = new Inner();
19         in.show();
20     }
21
22 }
23 */
24 class Outer {
25     int num = 3;
26     Object method(final int y) {
27
28         final int x = 9;
29         class Inner {
30             void show() {
31                 System.out.println("show..."+y);
32             }
33         }
34
35         Object in = new Inner();
36         return in;
37     }
38
39 }
40
41 /*多态
42 class Fu extends Object {
43
44 }
45 class zi extends Fu {
46
47 }
48 Fu f = new zi();
49 Object o = new Fu();
50 */
51 public class InnerClassDemo3 {
52     public static void main(String[] args) {
53         //new Outer().method();
54         Outer outer = new Outer();
55         Object object = outer.method(5);
56     }
57 }