假设有以下代码:interface IFace{ }class CFace implements IFace{ }class Base{ }public class ObRef extends Base{public static void main( String[] args ){ObRef obj = new ObRef( );Base b = new Base( );Object obj1 = new Object( );IFace obj2 = new CFace( );//Here}}则在//Here处插入()代码将不出现编译和运行错误。
A. obj1 = obj2;
B. b = obj;
C. obj = b;
D. obj1 = b;
已定义接口InterfaceB和InterfaceC,以下语句正确的是()。
A. interface A extends InterfaceB, InterfaceC
B. interface A implements InterfaceB, InterfaceC
C. class A implements InterfaceB, InterfaceC
D. class A implements InterfaceB, implements InterfaceC
(专升本)Java中允许接口的多继承,多个接口之间使用逗号分开。
A. 对
B. 错
写出程序的运行结果:interface A{float v = 2.0f;void init( );}class B{int v = 3;void output( ){System.out.println(v);}}class Test extends B implements A {public void init( ){System.out.println( "do init");}public static void main(String[] args){Test x = new Test( );x.init( );x.output( );x.printV( );}void printV( ){System.out.println( super.v + A.v);}}