单选题class A { public A() { System.out.println(“hello from a”); } } class B extends A { public B () { System.out.println(“hello from b”); super(); } } public class Test { public static void main(String args[]) { A a = new B(); } } What is the result when main is executed?()A Compilation fails.B hello from aC hello from bD hello from b hello from aE hello from a hello from b
单选题
class A { public A() { System.out.println(“hello from a”); } } class B extends A { public B () { System.out.println(“hello from b”); super(); } } public class Test { public static void main(String args[]) { A a = new B(); } } What is the result when main is executed?()
A
Compilation fails.
B
hello from a
C
hello from b
D
hello from b hello from a
E
hello from a hello from b
参考解析
解析:
Call to super must be first statement in constructor.
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