多项选择题
现有:
class ClassA {}
class ClassB extends ClassA {)
class ClassC extends ClassA {)
以及:
ClassA p0=new ClassA();
ClassB pl=new ClassB();
ClassC p2=new ClassC();
ClassA p3=new ClassB();
ClassA p4=new ClassC();
下列哪些是正确的?()
A.p0=pl;
B.p1 =p2;
C.p2=p4;
D.p2 = (ClassC)pl;
E.p1 = (ClassB)p3;
F.p2 = (Classc)p4;
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A. hi hi ouch!
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单项选择题
现有: class A {public String name="a"} class B extends A {public String name="b"} 执行如下代码后的结果是哪项?() A a=new B(); System.out.println(a.name);
A. a
B. b
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D.运行时抛出异常
