public interface Joy ( public void happySign(); } public class Man implements Joy { public Man () { } public void happySign () { System.out.println("smiles"); } public void sadSign () { } System.out.println("frowns"); public class Dog implements Joy ( public Dog () {} public void happySign () { } a) Joy obj1 = new Man(); obj1.sadSign(); System.out.println("wags tail"); public class GuardDog extends Dog { public GuardDog () { } public void happySign () { System.out.println("barks"); } public void angrySign () { } System.out.println("growls"); If the following lines of code appeared in the main method of a driver program, would the program compile and run? (yes or no?) If no, write 1-2 sentences to explain why not. If yes, indicate what the output would be.

public interface Joy ( public void happySign(); } public class Man implements Joy { public Man () { } public void happySign () { System.out.println("smiles"); } public void sadSign () { } System.out.println("frowns"); public class Dog implements Joy ( public Dog () {} public void happySign () { } a) Joy obj1 = new Man(); obj1.sadSign(); System.out.println("wags tail"); public class GuardDog extends Dog { public GuardDog () { } public void happySign () { System.out.println("barks"); } public void angrySign () { } System.out.println("growls"); If the following lines of code appeared in the main method of a driver program, would the program compile and run? (yes or no?) If no, write 1-2 sentences to explain why not. If yes, indicate what the output would be.

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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