which of the following is valid? public class Left{ public Left x; public void foo(){ System.out.println("Left"); public class Middle extends Left{ public Right y; public void foo(){ System.out.println("Middle"); } public class Right{ public Middle z; Select one: O Middle v3 = new Left (); v3.y = new Right(); O Left vl; v1.x = new Left (); O Left v2 = new Middle (); v2.x = new Left (); O None of these options

which of the following is valid? public class Left{ public Left x; public void foo(){ System.out.println("Left"); public class Middle extends Left{ public Right y; public void foo(){ System.out.println("Middle"); } public class Right{ public Middle z; Select one: O Middle v3 = new Left (); v3.y = new Right(); O Left vl; v1.x = new Left (); O Left v2 = new Middle (); v2.x = new Left (); O None of these options

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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Similar questions

How many methods and constructors do objects of type Middle have? public class Left{ public Left x; public void foo(){ System.out. println("Left"); } } public class Middle extends Left{ public Right y; public void foo(){ System.out. println("Middle"); } } public class Right{ public Middle z; } Select one: O Between 3 and 8 (that is, 3,4,5,6,7, or 8). More than 8 (that is, 9,10,11,.). Less than 3 (that is, 0 or 1 or 2). O None of these options
Given the following class definition: class Point2d { private int x, y; public Point2d () { X = 0; y = 0; } public Point2d (int i, int j) { X = i; y = j; } public void SetX (int i) { x = i; } public void SetY (int j) { y = j; } public int GetX () { return x; public int GetŸ () { return y; } public String toString() { return '[' + x + ", } + y + ']'; } } Use inheritance to create a class, Point3d, with any additional appropriate data and/or functions.
Find the error(s) in the following code snippet and explain how to correct it (them): 1 class Example { 2 public: Example(int y = 3 10) : data (y) {} 4 int getIncrementedData() const { return ++data; 7 } 8. 9 private: 10 int data; 11 };
// This class discounts prices by 10% public class DebugFour4 {    public static void main(String args[])    {       final double DISCOUNT_RATE = 0.90;       int price = 100;       double price2 = 100.00;       tenPercentOff(price DISCOUNT_RATE);       tenPercentOff(price2 DISCOUNT_RATE);    }    public static void tenPercentOff(int p, final double DISCOUNT_RATE)    {       double newPrice = p * DISCOUNT_RATE;       System.out.println("Ten percent off  " + p);       System.out.println("  New price is " + newPrice);    }    public static void tenPercentOff(double p, final double DISCOUNT_RATE)    {       double newPrice = p * DISCOUNT_RATE;       System.out.println"Ten percent off " + p);       System.out.println("  New price is " + newprice);    } }
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Advanced Object Concepts. I need help in understanding this solution, how everything works and relates with each other.