1.12 Homework

• Homework
• Scenario
  • Its your first day of class when Mr. Mortenson asks you to identify all the students and list some characteristics about them. Create a class to use as a template to create student objects and create 3 imaginary students.
• Instructions
• New Scenario
  • You find out that one of the students that you created an object for goes by a nickname. Using your knowledge of reference variables, create another object that references back to the same student.
• Instructions

// TODO: Finish and run in your Java environment
class Book {
    String title;
    int pages;

    void printInfo() {
        System.out.println("Title: " + title + ", Pages: " + pages);
    }
}

class MainPopcorn {
    public static void main(String[] args) {
        Book myBook = new Book();
        myBook.title = "The Great Gatsby";
        myBook.pages = 180;
        myBook.printInfo();
    }
}

// ## Quick Self-Check (concepts)
// 1. In one sentence, explain **class vs. object**.
   // - A **class** is a blueprint for creating objects, defining their properties and behaviors, while an **object** is an instance of a class that represents a specific entity with its own state and behavior.

// 2. What does a **reference variable** store?
   //   - A **reference variable** stores the memory address of an object, allowing access to the object's properties and methods.

   // 3. Name one method every object has because it extends **`Object`**.
   //   - One method every object has is **`toString()`**, which returns a string representation of the object.

Homework

---

Scenario

Its your first day of class when Mr. Mortenson asks you to identify all the students and list some characteristics about them. Create a class to use as a template to create student objects and create 3 imaginary students.

Instructions

1. Create a class
   • Instance variables:
   • String name
   • int grade
   • int pets
   • int siblings
   • MAKE YOUR OWN
2. In main:
   • Create three student objects.

//Code Here

public class StudentDemo {

    // Define the Student class
    static class Student {
        // Instance variables
        String name;
        int grade;
        int pets;
        int siblings;
        String favoriteSubject; // your own custom variable

        // Constructor
        Student(String name, int grade, int pets, int siblings, String favoriteSubject) {
            this.name = name;
            this.grade = grade;
            this.pets = pets;
            this.siblings = siblings;
            this.favoriteSubject = favoriteSubject;
        }

        // Method to display student info
        void displayInfo() {
            System.out.println("Name: " + name);
            System.out.println("Grade: " + grade);
            System.out.println("Pets: " + pets);
            System.out.println("Siblings: " + siblings);
            System.out.println("Favorite Subject: " + favoriteSubject);
            System.out.println("--------------------------");
        }
    }

    // Main method
    public static void main(String[] args) {
        // Create three student objects
        Student s1 = new Student("Ava", 10, 1, 2, "Biology");
        Student s2 = new Student("Liam", 11, 0, 1, "Computer Science");
        Student s3 = new Student("Sophia", 9, 3, 0, "History");

        // Display their information
        s1.displayInfo();
        s2.displayInfo();
        s3.displayInfo();
    }
}

New Scenario

You find out that one of the students that you created an object for goes by a nickname. Using your knowledge of reference variables, create another object that references back to the same student.

Instructions

1. Use your previous code

2. In main:

   • Create a reference variable with a different name that points to the same student.
   • Output the instance attributes of this student

public class StudentDemo {

    // Define the Student class
    static class Student {
        String name;
        int grade;
        int pets;
        int siblings;
        String favoriteSubject;

        // Constructor
        Student(String name, int grade, int pets, int siblings, String favoriteSubject) {
            this.name = name;
            this.grade = grade;
            this.pets = pets;
            this.siblings = siblings;
            this.favoriteSubject = favoriteSubject;
        }

        // Display student info
        void displayInfo() {
            System.out.println("Name: " + name);
            System.out.println("Grade: " + grade);
            System.out.println("Pets: " + pets);
            System.out.println("Siblings: " + siblings);
            System.out.println("Favorite Subject: " + favoriteSubject);
            System.out.println("--------------------------");
        }
    }

    public static void main(String[] args) {
        // Create three student objects
        Student s1 = new Student("Ava", 10, 1, 2, "Biology");
        Student s2 = new Student("Liam", 11, 0, 1, "Computer Science");
        Student s3 = new Student("Sophia", 9, 3, 0, "History");

        // Create a reference variable pointing to the same student
        Student nickname = s1;  // 'nickname' now refers to the same object as 's1'

        // Change the name to reflect the nickname
        nickname.name = "A.J.";

        // Display using both references
        System.out.println("Displaying s1 info:");
        s1.displayInfo();

        System.out.println("Displaying nickname info (same object):");
        nickname.displayInfo();
    }
}