``` enum Topic{ A, B; int e; int ec; public int getA() { return e; } } public class ScannerTest { public static void main(String[] args)throws Exception{ test(); } public static void test(){ System.out.println(Topic.A.e); System.out.println(Topic.B.e); System.out.println("---set t1 = Topic.A;---"); Topic t1 =Topic.A; System.out.println(t1.e); System.out.println("---before:t1.e =3;---"); t1.e=3; System.out.println(t1.e); System.out.println(Topic.A.e); System.out.println("--- get Topic.B;---"); Topic t2 =Topic.B; System.out.println(t2.e); System.out.println("--- get Topic.A;---"); Topic t3 =Topic.A; System.out.println(t3.e); } } 输出： 0 0 ---set t1 = Topic.A;--- 0 ---before:t1.e =3;--- 3 3 --- get Topic.B;--- 0 --- get Topic.A;--- 3 ```