Read the description of the class hierarchy below. It describes the relationship between four classes named A, B, C, and D. Class Hierarchy: class A extends Object class B extends A class C extends B class D extends B (The diagram looks like this) B Now consider this code. It declares some references, and then it has six assignment statements. Some of the assignment statements are illegal because the type of the reference on the left of the assignment would not work for storing the object on the right. For your answer, rewrite this code (feel free to copy and paste), leaving out any illegal statements: A a; B[] bArray; c c; D d; a = new B(); c = new C(); c = new A(); bArray new B[5]; bArray[4] = new D(); bArray[0] = new A();

Read the description of the class hierarchy below. It describes the relationship between four classes named A, B, C, and D. Class Hierarchy: class A extends Object class B extends A class C extends B class D extends B (The diagram looks like this) B Now consider this code. It declares some references, and then it has six assignment statements. Some of the assignment statements are illegal because the type of the reference on the left of the assignment would not work for storing the object on the right. For your answer, rewrite this code (feel free to copy and paste), leaving out any illegal statements: A a; B[] bArray; c c; D d; a = new B(); c = new C(); c = new A(); bArray new B[5]; bArray[4] = new D(); bArray[0] = new A();

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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Novice: How can i access a main class objects from outside the function? / Better Alternative? If i have 4 Student objects how can i print the information for the specific object given one parameter about the class, like the students Idnumber. What i came up with was making a checkId void function that takes the user input and runs an if else chain checking if the Id belongs to student 1-4 then printing the details of that classes object with the void function print. ideally i would want the if-else chain in the checkId function to call the print( student1-4) class object but im not sure how to properly do that. i dont think this is the best way to go about it, if you have any recommendations or alternatives please help me out.
User-defined Class:You will design and implement your own data class. The class will store data that has been read asuser input from the keyboard (see Getting Input below), and provide necessary operations. As thedata stored relates to monetary change, the class should be named Change. The class requires atleast 2 instance variables for the name of a person and the coin change amount to be given to thatperson. You may also wish to use 4 instance variables to represent amounts for each of the 4 coindenominations (see Client Class below). There should be no need for more than these instancevariables. However, if you wish to use more instance variables, you must provide legitimatejustification for their usage in the internal and external documentation.Your class will need to have at least a default constructor, and a constructor with two parameters:one parameter being a name and the other a coin amount. Your class should also provide appropriateget and set methods for client usage. Other…
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This assignment contains both lesson assignment and lab task (The same problem is assignment as well lab task)The assignment contains topic: (Class, objects, access specifier, multiple class files, logic building, UML, constructors, memory management, this keyword and static keyword, etc)
Goal 1: Update the Fractions Class Here we will overload two functions that will used by the Recipe class later: multipliedBy, dividedBy Previously, these functions took a Fraction object as a parameter. Now ADD an implementation that takes an integer as a parameter. The functionality remains the same: Instead of multiplying/dividing the current object with another Fraction, it multiplies/divides with an integer (affecting numerator/denominator of the returned object). For example; a fraction 2/3 when multiplied by 4 becomes 8/3. Similarly, a fraction 2/3 when divided by 4 becomes 1/6. Goal 2: Update the Recipe Class Now add a private member variable of type int to denote the serving size and initialize it to 1. This means all recipes are initially constructed for a single serving. Update the overloaded extraction operator (<<) to include the serving size (sample output below for an example of formatting) . New Member functions to the Recipe Class: 1. Add four member functions…
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please help This class describes a tweet. A tweet has a message in it, a unique ID,* a count of the number of likes, and a count of the number of times it* has been retweeted. In addition, the Tweet class will have a static * variable to count the total number of tweets to ever be created * (retweets don't count as a new tweet).* * You may NOT import any library class.* **/public class Tweet {
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Help of what these errors mean. In C# • Create a Class, named Student, to hold properties of Student Last Name, Student First Name, Student ID (9 digits), Course Prefix and Number, and the tests (Test 1, Test 2, Test 3, Test 4). Create appropriate setter and getter accessors, and constructors. Use access modifiers. Example: First Name : Pat Last Name : Smythe Student ID : ABC111333 Course Prefix : CIST Course Name : 2431 Test 1 : 100 Test 2 : 90 Test 3 : 80 Test 4 : 88 • Prompt the user for the Student Last and First Name, Student ID, Course Prefix and Number and the tests. • Include at least one exception handling function. • Use an array to store the 4 test grades. • Use a looping structure to populate the array. • Calculate the numeric average based upon the 4 equally-weighted numeric grades. • Display all the data for each of student using a looping structure. • Display the numeric average for each student. • Create a function that will convert the numeric average to a…