Class Exercise: Constructor using JAVA Let’s define a Class together and have a constructor while at...

Class Exercise: Constructor using JAVA

Let’s define a Class together and have a constructor while at it.

- What should the Class object represent? (What is the “real life object” to represent)?

- What properties should it have? (let’s hold off on the methods/actions for now – unless necessary for the constructor)

- What should happen when a new instance of the Class is created?

- Question: What are you allowed to do in the constructor?

- Let’s test this out (demo).

Expert Solution

The Class in any Object Oriented Programming Language represents a template or a blue print.

So an object of that class is an instance of a class.

Class has just logical existence but an object has physical existence.

When an object is created, the space required for the object is allocated. Any constructors that class has are executed on the object. The constructor should have the same name as the class.

We can initialise the variables, allocate memory.

Please find below the demo program.

import java.util.*;
import java.lang.*;
import java.io.*;

class sample
{
   int demo;

   sample()
   {
       demo=100;   //the variable is initialised using the constructor.
   }

   void display()
   {
       System.out.println("Demo value is "+demo);
   }
   }
class Demo_class
{
   public static void main (String[] args) throws java.lang.Exception
   {

       sample s=new sample();   //a new object is created.

       s.display();

   }
}

venereology answered 3 years ago

IN JAVA PLEASE The Palindrome class will have a single constructor that accepts a String argument...

IN JAVA PLEASE The Palindrome class will have a single constructor that accepts a String argument and checks to see if the String is a palindrome. If it is a palindrome it will store the palindrome and the original String as state values. If is not a palindrome it will throw a “NotPalindromeError” and not finish the creation of the new Palindrome object. The constructor will use a single stack to evaluate if the String is a palindrome. You must...

Using Java: Create a class called MyNumber with an integer private attribute. Create a constructor that...

Using Java: Create a class called MyNumber with an integer private attribute. Create a constructor that defines an integer parameter to set the private integer attribute. Create a setter that validates the attribute does not accept a value lower than 2 or the method will throw a IllegalArgumetException. Create a getter to return the private integer attribute value. Define a public method that is called isPrime() that returns a boolean and implements the Sieve of Eratosthenes method. Define a public...

JAVA The class will have a constructor BMI(String name, double height, double weight). The class should...

JAVA The class will have a constructor BMI(String name, double height, double weight). The class should have a public instance method, getBMI() that returns a double reflecting the person's BMI (Body Mass Index = weight (kg) / height2 (m2) ). The class should have a public toString() method that returns a String like Fred is 1.9m tall and is 87.0Kg and has a BMI of 24.099722991689752Kg/m^2 (just print the doubles without special formatting). Implement this class (if you wish you...

in java Create a class City with x and y as the class variables. The constructor...

in java Create a class City with x and y as the class variables. The constructor with argument will get x and y and will initialize the city. Add a member function getDistanceFrom() to the class that gets a city as the input and finds the distance between the two cities.

- Create a java class named SaveFile in which write the following: Constructor: The class's constructor...

- Create a java class named SaveFile in which write the following: Constructor: The class's constructor should take the name of a file as an argument A method save (String line): This method should open the file defined by the constructor, save the string value of line at the end of the file, and then close the file. - In the same package create a new Java class and it DisplayFile in which write the following: Constructor: The class's constructor...

using java Define a class Library based on the following specifications: a. A library can have...

using java Define a class Library based on the following specifications: a. A library can have multiple books. Decide on the best possible data structure to store books. b. A library has a name. c. A library has an address. Define a 2-argument constructor for the Library class. Decide on the arguments needed for this constructor. e. Define a method that can add new books to the library. f. Define a method that allows a book to be borrowed (checked...

Define the exception class called TornadoException. The class should have two constructors including one default constructor....

Define the exception class called TornadoException. The class should have two constructors including one default constructor. If the exception is thrown with the default constructor, the method getMessage should return "Tornado: Take cover immediately!" The other constructor has a single parameter, m, of int type. If the exception is thrown with this constructor, the getMessage should return "Tornado: m miles away; and approaching!" Write a Java program to test the class TornadoException.

JavaScript - Create a class using "names" as the identifier. Create a constructor. The constructor must...

JavaScript - Create a class using "names" as the identifier. Create a constructor. The constructor must have elements as follow: first ( value passed will be String ) last ( value passed will be String ) age ( value passed will be Numeric ) The constructor will assign the values for the three elements and should use the "this" keyword Create a function, using "printObject" as the identifier printObject: This function will have three input parameters: allNames , sortType, message...

Define empty methods in Queue class using LinkedList class in Java ------------------------------------------------------------------------------- //Queue class public class...

Define empty methods in Queue class using LinkedList class in Java ------------------------------------------------------------------------------- //Queue class public class Queue{ public Queue(){ // use the linked list } public void enqueue(int item){ // add item to end of queue } public int dequeue(){ // remove & return item from the front of the queue } public int peek(){ // return item from front of queue without removing it } public boolean isEmpty(){ // return true if the Queue is empty, otherwise false }...

Define empty methods in Stack class using LinkedList class in Java ------------------------------------------------------------------------------- //Stack class public class...

Define empty methods in Stack class using LinkedList class in Java ------------------------------------------------------------------------------- //Stack class public class Stack{ public Stack(){ // use LinkedList class } public void push(int item){ // push item to stack } public int pop(){ // remove & return top item in Stack } public int peek(){ // return top item in Stack without removing it } public boolean isEmpty(){ // return true if the Stack is empty, otherwise false } public int getElementCount(){ // return current number...

Question