Additional Practice

Code challenge 1

Write the code for the alternative constructor, then write the main() method to accept input from the user through the keyboard and invoke the object using these values

Answer

java

Code challenge 2

Write a class called Calculator. The program will accept two numbers from the user through the keyboard and provide a list of mathematical operations which must be performed on the two number provided. The program then provides the result to the user on the screen. The available mathematical operations are as follows:

Addition (+)
Subtraction (-)
Multiplication (*)
Division (/)
Modulus (%)

The method must make use of the switch statement to perform the operations

Answer

import java.util.Scanner; /** * The Movie class represents a movie with its name, duration, and production company. * It provides constructors, accessors, mutators, and a method to display movie details. * * @author Jimmy * @version 1.0 */ public class Movie { // Fields private String name; private double duration; private String company; /** * Default constructor that initializes the movie details with default values. */ public Movie() { name = ""; duration = 0.0; company = ""; } /** * Constructs a Movie object with the specified name, duration, and production company. * * @param movieName the name of the movie. * @param movieDuration the duration of the movie in hours. * @param movieCompany the production company of the movie. */ public Movie(String movieName, double movieDuration, String movieCompany) { this.name = movieName; this.duration = movieDuration; this.company = movieCompany; } /** * Displays the details of the movie. */ public void display() { System.out.println("Movie Name: " + name); System.out.println("Duration: " + duration + " hours"); System.out.println("Production Company: " + company); } /** * Returns the production company of the movie. * * @return the production company. */ public String getCompany() { return company; } /** * Returns the duration of the movie in hours. * * @return the duration of the movie. */ public double getDuration() { return duration; } /** * Returns the name of the movie. * * @return the movie name. */ public String getName() { return name; } /** * The main method creates a Movie object based on user input and displays its details. * * @param args command-line arguments (not used). */ public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.print("Enter movie name: "); String inputName = scanner.nextLine(); System.out.print("Enter duration (in hours): "); double inputDuration = scanner.nextDouble(); scanner.nextLine(); // Consume the newline left by nextDouble() System.out.print("Enter production company: "); String inputCompany = scanner.nextLine(); Movie movie = new Movie(inputName, inputDuration, inputCompany); movie.display(); scanner.close(); } /** * Sets the production company of the movie. * * @param newCompany the new production company. */ public void setCompany(String newCompany) { company = newCompany; } /** * Sets the duration of the movie. * * @param newDuration the new duration in hours. */ public void setDuration(double newDuration) { duration = newDuration; } /** * Sets the name of the movie. * * @param newName the new movie name. */ public void setName(String newName) { name = newName; } }

import java.util.Scanner; /** * The Calculator class accepts two numbers from the user and performs * a selected mathematical operation. Available operations include: * <ul> * <li>Addition (+)</li> * <li>Subtraction (-)</li> * <li>Multiplication (*)</li> * <li>Division (/)</li> * <li>Modulus (%)</li> * </ul> * * The result of the selected operation is displayed on the screen. * * @author Jimmy * @version 1.0 */ public class Calculator { /** * Default constructor. */ public Calculator() { } /** * The main method reads two numbers and an operator from the user, * performs the corresponding mathematical operation, and displays the result. * * @param args command-line arguments (not used) */ public static void main(String[] args) { Scanner scanner = new Scanner(System.in); System.out.print("Enter the first number: "); double num1 = scanner.nextDouble(); System.out.print("Enter the second number: "); double num2 = scanner.nextDouble(); scanner.nextLine(); // Consume newline left-over System.out.println("Select an operation:"); System.out.println(" + : Addition"); System.out.println(" - : Subtraction"); System.out.println(" * : Multiplication"); System.out.println(" / : Division"); System.out.println(" % : Modulus"); System.out.print("Enter an operation: "); char operator = scanner.nextLine().charAt(0); double result; switch (operator) { case '+': result = num1 + num2; System.out.println("Result: " + result); break; case '-': result = num1 - num2; System.out.println("Result: " + result); break; case '*': result = num1 * num2; System.out.println("Result: " + result); break; case '/': if (num2 == 0) { System.out.println("Error: Division by zero is not allowed."); } else { result = num1 / num2; System.out.println("Result: " + result); } break; case '%': if (num2 == 0) { System.out.println("Error: Modulus by zero is not allowed."); } else { result = num1 % num2; System.out.println("Result: " + result); } break; default: System.out.println("Invalid operator! Please select one of +, -, *, /, or %."); break; } scanner.close(); } @Override public String toString() { return "This is a calculator"; } }

学习

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Additional Practice

Code challenge 1

Answer

Code challenge 2

Answer

本页目录

学习

Additional Practice

Code challenge 1

Answer

Code challenge 2

Answer

本页目录