Parameterized constructors

A parameterized constructor accepts arguments to initialize an object with specific values.

Example:

class Student {
    String name;
    int id;
    double grade;

    // Parameterized constructor
    Student(String name, int id, double grade) {
        this.name = name;
        this.id = id;
        this.grade = grade;
    }
}

Student s1 = new Student("Alice", 101, 85.5);
Student s2 = new Student("Bob", 102, 92.0);

Benefits:

• Allows creating objects with different initial states.
• Reduces the need for setter methods after creation.
• Makes objects immediately usable.

Multiple parameterized constructors: Use overloading (different parameter lists).

Student(String name, int id) {
    this(name, id, 0.0);  // calling another constructor
}