Practice 70 Java Constructor Programming Questions

Practice 70 Java Constructor Programming Questions

Q1. Write a Java program to create a constructor that initializes a string.
   Input:  
   Enter a string: Hello, World!

   Expected Output:      
   The string is: Hello, World!

Q2. Write a Java program to create a constructor that accepts two integers and calculates their sum.
   Input:  
   Enter two integers: 5 10

   Expected Output:      
   The sum is: 15

Q3. Write a Java program to demonstrate the use of a default constructor.
   Expected Output:  
   Default Constructor Called

Q4. Write a Java program to create a constructor that accepts a name and age, then displays them.
   Input:  
   Enter name: John
   Enter age: 25

   Expected Output:     
   Name: John
   Age: 25

Q5. Write a Java program to create a constructor that initializes a circle’s radius and calculates its area.
   Input:  
   Enter radius: 7

   Expected Output:      
   Area of the circle is: 153.93804002589985

Q6. Write a Java program to create a constructor that initializes a rectangle’s length and width, then calculates its area.
   Input:  
   Enter length: 5
   Enter width: 3

   Expected Output:      
   Area of the rectangle is: 15

Q7. Write a Java program to create a constructor that initializes an object with a string and an integer, then displays them.
   Input:  
   Enter string: Java
   Enter number: 10

   Expected Output:      
   String: Java
   Number: 10

Q8. Write a Java program to create a constructor that accepts two integers and calculates their product.
   Input:  
   Enter two integers: 6 4

   Expected Output:      
   The product is: 24

Q9. Write a Java program to demonstrate constructor overloading with two constructors.
   Input:  
   Enter a number: 5

   Expected Output:      
   Constructor with one parameter called

Q10. Write a Java program to create a constructor that initializes a person’s name, age, and city.
   Input:  
   Enter name: Alice
   Enter age: 30
   Enter city: New York

   Expected Output:      
   Name: Alice
   Age: 30
   City: New York

Q11. Write a Java program to create a constructor that initializes a vehicle’s brand and model.
   Input:  
   Enter brand: Toyota
   Enter model: Corolla

   Expected Output:      
   Brand: Toyota
   Model: Corolla

Q12. Write a Java program to create a constructor that accepts an array of integers and calculates their sum.
   Input:  
   Enter the number of elements: 5
   Enter elements: 1 2 3 4 5

   Expected Output:      
   The sum of the array is: 15

Q13. Write a Java program to create a constructor that initializes a book’s title and price.
   Input:  
   Enter title: Java Programming
   Enter price: 29.99

   Expected Output:      
   Title: Java Programming
   Price: 29.99

Q14. Write a Java program to create a constructor that initializes an employee’s ID and salary.
   Input:  
   Enter employee ID: 101
   Enter salary: 50000

   Expected Output:      
   Employee ID: 101
   Salary: 50000

Q15. Write a Java program to create a constructor that initializes a student’s name, age, and grade.
   Input:  
   Enter name: Bob
   Enter age: 20
   Enter grade: A

   Expected Output:      
   Name: Bob
   Age: 20
   Grade: A

Q16. Write a Java program to create a constructor that accepts a date of birth and calculates the age.
   Input:  
   Enter date of birth (yyyy-mm-dd): 2000-01-01

   Expected Output:      
   Age is: 25

Q17. Write a Java program to create a constructor that initializes a bank account with an account number and balance.
   Input:  
   Enter account number: 12345
   Enter balance: 1000

   Expected Output:      
   Account Number: 12345
   Balance: 1000

Q18. Write a Java program to create a constructor that initializes a point’s x and y coordinates.
   Input:  
   Enter x coordinate: 2
   Enter y coordinate: 3

   Expected Output:      
   Point coordinates: (2, 3)

Q19. Write a Java program to create a constructor that initializes a product’s name and price.
   Input:  
   Enter product name: Laptop
   Enter price: 700

   Expected Output:      
   Product Name: Laptop
   Price: 700

Q20. Write a Java program to create a constructor that initializes a circle’s radius and calculates its circumference.
   Input:  
   Enter radius: 5

   Expected Output:      
   Circumference of the circle is: 31.41592653589793

Q21. Write a Java program to create a constructor that accepts the radius and calculates the area and circumference of a circle.
   Input:  
   Enter radius: 10

   Expected Output:      
   Area: 314.1592653589793
   Circumference: 62.83185307179586

Q22. Write a Java program to create a constructor that initializes a book with title, author, and year.
   Input:  
   Enter title: Effective Java
   Enter author: Joshua Bloch
   Enter year: 2008

   Expected Output:      
   Title: Effective Java
   Author: Joshua Bloch
   Year: 2008

Q23. Write a Java program to create a constructor that initializes a person’s first name and last name.
   Input:  
   Enter first name: John
   Enter last name: Doe

   Expected Output:      
   Full name: John Doe

Q24. Write a Java program to create a constructor that initializes a car’s brand, model, and year.
   Input:  
   Enter brand: Ford
   Enter model: Mustang
   Enter year: 2022

   Expected Output:      
   Brand: Ford
   Model: Mustang
   Year: 2022

Q25. Write a Java program to create a constructor that initializes an employee’s name, position, and salary.
   Input:  
   Enter name: Alice
   Enter position: Manager
   Enter salary: 80000

   Expected Output:      
   Name: Alice
   Position: Manager
   Salary: 80000

Q26. Write a Java program to create a constructor that initializes a student’s roll number and grade.
   Input:  
   Enter roll number: 101
   Enter grade: A

   Expected Output:      
   Roll number: 101
   Grade: A

Q27. Write a Java program to create a constructor that accepts two numbers and finds the larger of the two.
   Input:  
   Enter first number: 5
   Enter second number: 8

   Expected Output:      
   The larger number is: 8

Q28. Write a Java program to create a constructor that initializes a time in hours and minutes, then calculates total minutes.
   Input:  
   Enter hours: 2
   Enter minutes: 30

   Expected Output:      
   Total minutes: 150

Q29. Write a Java program to create a constructor that accepts the name of a student and their marks in 3 subjects, and calculates the average.
   Input:  
   Enter name: Jane
   Enter marks for 3 subjects: 85 90 88

   Expected Output:      
   Name: Jane
   Average marks: 87.67

Q30. Write a Java program to create a constructor that initializes a product’s name, quantity, and price, and calculates total cost.
   Input:  
   Enter product name: Phone
   Enter quantity: 2
   Enter price: 300

   Expected Output:      
   Product: Phone
   Total cost: 600

Q31. Write a Java program to create a constructor that initializes a rectangle with width and height, then calculates the perimeter.
   Input:  
   Enter width: 4
   Enter height: 6

   Expected Output:      
   Perimeter of the rectangle is: 20

Q32. Write a Java program to create a constructor that initializes a person's name and date of birth, then calculates their age.
   Input:  
   Enter name: David
   Enter date of birth (yyyy-mm-dd): 1995-05-10

   Expected Output:      
   Name: David
   Age: 29

Q33. Write a Java program to create a constructor that accepts two floating-point numbers and performs subtraction.
   Input:  
   Enter first number: 10.5
   Enter second number: 4.3

   Expected Output:      
   The result of subtraction is: 6.2

Q34. Write a Java program to create a constructor that initializes a book’s title, author, and price.
   Input:  
   Enter title: Java Basics
   Enter author: Jane Smith
   Enter price: 25.5

   Expected Output:      
   Title: Java Basics
   Author: Jane Smith
   Price: 25.5

Q35. Write a Java program to create a constructor that initializes a number and calculates its square.
   Input:  
   Enter a number: 6

   Expected Output:      
   The square of 6 is: 36

Q36. Write a Java program to create a constructor that accepts a person's first name and last name, then displays the full name.
   Input:  
   Enter first name: Sarah
   Enter last name: Connor

   Expected Output:      
   Full name: Sarah Connor

Q37. Write a Java program to create a constructor that accepts an integer and calculates its factorial.
   Input:  
   Enter an integer: 5

   Expected Output:      
   The factorial of 5 is: 120

Q38. Write a Java program to create a constructor that initializes a cube’s side length and calculates its volume.
   Input:  
   Enter side length: 3

   Expected Output:      
   Volume of the cube is: 27

Q39. Write a Java program to create a constructor that initializes a book’s name and its number of pages, then displays the total pages.
   Input:  
   Enter book name: Programming 101
   Enter number of pages: 200

   Expected Output:      
   Book: Programming 101
   Pages: 200

Q40. Write a Java program to create a constructor that initializes a person’s name, city, and country.
   Input:  
   Enter name: Olivia
   Enter city: Paris
   Enter country: France

   Expected Output:      
   Name: Olivia
   City: Paris
   Country: France

Q41. Write a Java program to create a constructor that initializes a student's name and subject marks, then calculates total marks.
   Input:  
   Enter name: Peter
   Enter marks for 3 subjects: 78 89 95

   Expected Output:      
   Name: Peter
   Total Marks: 262

Q42. Write a Java program to create a constructor that initializes a time with hours and minutes and displays the total minutes.
   Input:  
   Enter hours: 2
   Enter minutes: 45

   Expected Output:      
   Total minutes: 165

Q43. Write a Java program to create a constructor that accepts a salary and calculates the tax.
   Input:  
   Enter salary: 5000

   Expected Output:      
   Tax is: 500

Q44. Write a Java program to create a constructor that initializes a vehicle’s model and price.
   Input:  
   Enter model: BMW X5
   Enter price: 60000

   Expected Output:      
   Model: BMW X5
   Price: 60000

Q45. Write a Java program to create a constructor that accepts an integer and finds whether it is even or odd.
   Input:  
   Enter a number: 7

   Expected Output:      
   The number 7 is odd.

Q46. Write a Java program to create a constructor that initializes a phone’s brand, model, and price.
   Input:  
   Enter brand: Samsung
   Enter model: Galaxy S21
   Enter price: 999.99

   Expected Output:      
   Brand: Samsung
   Model: Galaxy S21
   Price: 999.99

Q47. Write a Java program to create a constructor that initializes a person's name and displays a greeting message.
   Input:  
   Enter name: Emma

   Expected Output:      
   Hello, Emma! Welcome to Java Programming.

Q48. Write a Java program to create a constructor that initializes a time in hours, minutes, and seconds and displays the total seconds.
   Input:  
   Enter hours: 1
   Enter minutes: 30
   Enter seconds: 45

   Expected Output:      
   Total time in seconds: 5445

Q49. Write a Java program to create a constructor that initializes a product’s name, price, and quantity, and calculates total cost.
   Input:  
   Enter product name: Smartwatch
   Enter price: 199.99
   Enter quantity: 3

   Expected Output:      
   Product: Smartwatch
   Total cost: 599.97

Q50. Write a Java program to create a constructor that accepts a string and displays the number of characters in it.
   Input:  
   Enter a string: JavaProgramming

   Expected Output:      
   The string "JavaProgramming" has 15 characters.

Q51. Write a Java program to create a constructor that initializes a rectangle’s width and height and calculates its area.
   Input:  
   Enter width: 6
   Enter height: 8

   Expected Output:     
   Area of the rectangle: 48

Q52. Write a Java program to create a constructor that accepts a student's name and subject marks and calculates the percentage.
   Input:  
   Enter name: Michael
   Enter marks for 5 subjects: 85 90 78 88 92

   Expected Output:      
   Name: Michael
   Percentage: 86.6%

Q53. Write a Java program to create a constructor that initializes a circle’s radius and calculates its area and circumference.
   Input:  
   Enter radius: 4

   Expected Output:      
   Area: 50.26548245743669
   Circumference: 25.1327412287193

Q54. Write a Java program to create a constructor that initializes a triangle’s base and height and calculates its area.
   Input:  
   Enter base: 10
   Enter height: 5

   Expected Output:      
   Area of the triangle is: 25

Q55. Write a Java program to create a constructor that initializes an address with street, city, and zip code.
   Input:  
   Enter street: 123 Main St
   Enter city: Los Angeles
   Enter zip code: 90001

   Expected Output:      
   Address: 123 Main St, Los Angeles, 90001

Q56. Write a Java program to create a constructor that initializes a book’s title and author and displays them.
   Input:  
   Enter title: Java for Beginners
   Enter author: Alice Johnson

   Expected Output:      
   Title: Java for Beginners
   Author: Alice Johnson

Q57. Write a Java program to create a constructor that initializes a student’s name and calculates the average marks.
   Input:  
   Enter name: John
   Enter marks for 3 subjects: 75 80 70

   Expected Output:      
   Name: John
   Average Marks: 75.0

Q58. Write a Java program to create a constructor that accepts a product’s name, price, and quantity, and calculates the total price.
   Input:  
   Enter product name: Tablet
   Enter price: 150
   Enter quantity: 2

   Expected Output:      
   Product: Tablet
   Total price: 300

Q59. Write a Java program to create a constructor that initializes a person’s name and age and displays them.
   Input:  
   Enter name: Peter
   Enter age: 30

   Expected Output:      
   Name: Peter
   Age: 30

Q60. Write a Java program to create a constructor that accepts two integers and calculates their difference.
   Input:  
   Enter first integer: 9
   Enter second integer: 5

   Expected Output:      
   The difference is: 4

Q61. Write a Java program to create a constructor that initializes a movie’s name and director and displays them.
   Input:  
   Enter movie name: The Matrix
   Enter director: Wachowskis

   Expected Output:      
   Movie: The Matrix
   Director: Wachowskis

Q62. Write a Java program to create a constructor that accepts a point’s x and y coordinates and calculates the distance from the origin.
   Input:  
   Enter x coordinate: 3
   Enter y coordinate: 4

   Expected Output:      
   Distance from origin: 5.0

Q63. Write a Java program to create a constructor that initializes a city’s name and population, and displays them.
   Input:  
   Enter city name: Paris
   Enter population: 2148000

   Expected Output:      
   City: Paris
   Population: 2148000

Q64. Write a Java program to create a constructor that initializes a book’s title, author, and price, and displays them.
   Input:  
   Enter title: Advanced Java
   Enter author: Bob Martin
   Enter price: 50.99

   Expected Output:      
   Title: Advanced Java
   Author: Bob Martin
   Price: 50.99

Q65. Write a Java program to create a constructor that initializes a product’s name, price, and quantity and calculates the total cost.
   Input:  
   Enter product name: Laptop
   Enter price: 900.00
   Enter quantity: 2

   Expected Output:      
   Product: Laptop
   Total cost: 1800.0

Q66. Write a Java program to create a constructor that initializes a book’s title, author, and year of publication and displays them.
   Input:  
   Enter title: Java Programming
   Enter author: Mark Lee
   Enter year: 2021

   Expected Output:      
   Title: Java Programming
   Author: Mark Lee
   Year: 2021

Q67. Write a Java program to create a constructor that accepts two numbers and calculates the average.
   Input:  
   Enter first number: 12
   Enter second number: 18

   Expected Output:      
   Average: 15.0

Q68. Write a Java program to create a constructor that initializes a car’s brand, model, and price and displays them.
   Input:  
   Enter brand: Tesla
   Enter model: Model S
   Enter price: 79999

   Expected Output:      
   Brand: Tesla
   Model: Model S
   Price: 79999

Q69. Write a Java program to create a constructor that initializes a person's name and age and displays the name and calculates the decade.
   Input:  
   Enter name: Lucy
   Enter age: 25

   Expected Output:      
   Name: Lucy
   Decade: 20s

Q70. Write a Java program to create a constructor that initializes a product’s name, price, and quantity and calculates the total revenue.
   Input:  
   Enter product name: Smartphone
   Enter price: 400
   Enter quantity: 3

   Expected Output:      
   Product: Smartphone
   Revenue: 1200