How can we prevent the accidental mixing of non-object and object values by using wrapper classes for non-object data types?

In java Define and create an array (called emps) of object references for objects of class Employee of length 100. (b) Create three objects for classes SalariedEmp, WeeklyEmp, and HourlyEmp (where these 3 classes are subclasses of class Employee); and with references e1, e2, e3 for the 3 objects:(c) Assign e1,e2, e3 to the first three elements of array emps:(d) Print the earnings of the 100 employee in the array emps in one loop (with polymorphism) where earnings are calculated with method earnings():

The main differences between method overloading and method overriding should be clarified.

why might we write public get and set methods for private properties? hint: you may want to do a quick internet search for "java getters and setters pros and cons." 1. these public methods give us a way to read and write the values of these properties in a controlled way 2. they make a program run more efficiently 3. if we didn’t, there would be no way to read or write the values of the properties 4. object-oriented languages require us to do this

JAVA programming language

What is the main difference between a struct and a class?     (More than 1 answer can be chosen)

Please use this template /*************************************************************************  predefined classes, functions, structures*************************************************************************/#include <iostream>        // cin, cout// missing severalusing namespace std; /*************************************************************************  global formatting constants*************************************************************************/const unsigned int AUTHOR_COLUMN_WIDTH = 25;const unsigned int TITLE_COUNT_COLUMN_WIDTH = 18; /*************************************************************************  function prototypes*************************************************************************/void showMenu();void displayFirstFileLine(const string file_name);void displayFirstAuthorName(const string file_name);void displayFirstAuthorInformation(const string file_name);void displayAllAuthorInformation(const string file_name);void…

Javascript Create an object, Gremlin, that extends the Monster interface and takes the same argument language. Gremlins inherits how a monster eats. Gremlins speaks differently. Gremlins replace each word in a sentence with its only known language, "gar". For example, if the sentence is "I like chicken", the speak() method will turn it into "gar gar gar". class Monster { constructor(language){ this.language = language; this.stomach = Array(); } // takes a food_item STRING and returns everything eaten so far ARRAY eat(food_item) { this.stomach.push(food_item); }   // takes in a sentence STRING and returns the passed in sentence STRING with no change speak(sentence) { returnsentence; }   }

a:) Define a Polygon interface that has methods area() and perimeter(). b:) Then implement classes for Triangle, Quadrilateral, Pentagon, Hexagon, and Octagon, which implement this interface, with the obvious meanings for the area() and perimeter() methods. c:) Implement classes, IsoscelesTriangle, Equilateral-Triangle, Rectangle, and Square, which have the appropriate inheritance relationships. d:) Write a simple user interface, which allows users to create polygons of the various types, input their geometric dimensions, and then output their area and perimeter. e:) For extra effort, allow users to input polygons by specifying their vertex coordinates and be able to test if two such polygons are similar. using all a to e parts develop a program