Incorrect Question 4 Consider: interface I { } interface J { } } class A implements I { void doI(); } void doJ(); class B extends A { } public void doI() { } } class C implements J { public void doJ() { } public void doJ() { } class D implements I, J { public void doI() { } public void doJ() { } Which of the following are valid? ✓ 0 0 I x = new D(); I x = new B(); J x = new DO); J x = new J(); B x = new B(); x.doI(); I x = new A(); J x = new A(); J x = new C(); A x= new A(); x.doI(); I x = new C(); J x = new B(); A x= new A(); x.doJ(); I x = new I()); B x= new B(); x.doJ();

Incorrect Question 4 Consider: interface I { } interface J { } } class A implements I { void doI(); } void doJ(); class B extends A { } public void doI() { } } class C implements J { public void doJ() { } public void doJ() { } class D implements I, J { public void doI() { } public void doJ() { } Which of the following are valid? ✓ 0 0 I x = new D(); I x = new B(); J x = new DO); J x = new J(); B x = new B(); x.doI(); I x = new A(); J x = new A(); J x = new C(); A x= new A(); x.doI(); I x = new C(); J x = new B(); A x= new A(); x.doJ(); I x = new I()); B x= new B(); x.doJ();

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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