can you give me a background explanation i can use to approach this problem? Consider the three classes Alpha, Beta, and Gamma.Which of the following statement(s) is/are not legal in codethat uses these classes (choose all that apply)?Gamma a = new Gamma();Gamma b= new Alpha();Gamma c = new Beta();Alpha d = new Alpha();Beta e = new Beta();Alpha f = new Beta();public class Alpha extends Gamma {public String getTwo() {return("2");}public String getTwo(int i) {return("two");}}public class Beta extends Gamma{public String getThree() {return ("3");}public String getFour() {return ("four");}}public abstract class Gamma {public String getOne() {return ("1");}public String getFour() {return("4");}}

Java is an object oriented programming language.The statements which are not legal are as follows:- 1. Gamma a = new Gamma(); 2. Alpha f = new Beta(); Explanation:- The first statement is wrong as an Abstract class can only be initialised using it child class references and not by using its own. The second statement is wrong as Alpha class and Beta class are not related with other and hence Alpha class object cannot hold the reference of Beta class. Gamma class object can hold references of both Alpha and Beta class and Alpha class object can hold reference of Alpha class only and Beta class object can hold reference to the Beta class only.

Engineering

Computer Science

Consider the three classes Alpha, Beta, and Gamma. Which of the following statement(s) is/are not legal in code that uses these classes (choose all that apply)? Gamma a = new Gamma(); Gamma b = new Alpha(); Gamma c = new Beta(); Alpha d = new Alpha(); Beta e = new Beta(); Alpha f = new Beta();

Consider the three classes Alpha, Beta, and Gamma. Which of the following statement(s) is/are not legal in code that uses these classes (choose all that apply)? Gamma a = new Gamma(); Gamma b = new Alpha(); Gamma c = new Beta(); Alpha d = new Alpha(); Beta e = new Beta(); Alpha f = new Beta();

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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