Question

a teacher is creating a class that will help keep track of student grades. he will be using the following instance variables:

• studentname (string)
• studentgrade (double)
• lettergrade (string)

and this constructor:
public student(string n, double d, string g){
studentname = n;
studentgrade = d;
lettergrade = g;
}

which of the following would be the best way to create a student object?

• student s1 = new student(98.2, \a\, \ima coder\);
• student s1 = new student(\a\, \ima coder\, 98.2);
• student s1 = new student(\ima coder\, 98.2, \a\);

Explanation:

🆕 New Concept Discovered: Object Instantiation and Constructors
Matching arguments to constructor parameters.

Step 1: Analyze the Constructor Signature

The class constructor defines the exact order and data types of the values (arguments) you must pass when creating a new object:

public Student(String n, double d, String g)

This signature tells us the constructor expects three parameters in this specific order:

1. A String value for the name (n)
2. A double (decimal number) value for the grade (d)
3. A String value for the letter grade (g)

Step 2: Evaluate the Options

We need to find the option where the arguments match the required sequence: (String, double, String).

• Option 1: Student s1 = new Student(98.2, "A", "Ima Coder");
• Types passed: (double, String, String) $

ightarrow$ Incorrect order

• Option 2: Student s1 = new Student("A", "Ima Coder", 98.2);
• Types passed: (String, String, double) $

ightarrow$ Incorrect order

• Option 3: Student s1 = new Student("Ima Coder", 98.2, "A");
• Types passed: (String, double, String) $

ightarrow$ Correct order

Answer:

Student s1 = new Student("Ima Coder", 98.2, "A");