Creating Constructors
A constructor initializes an object when it's created. It has the same name as the class and no return type.
Example
public class User {
private String name;
private String email;
private int age;
// Default constructor
public User() {
this.name = "Unknown";
this.email = "";
this.age = 0;
}
// Parameterized constructor
public User(String name, String email, int age) {
this.name = name;
this.email = email;
this.age = age;
}
// Constructor chaining with this()
public User(String name, String email) {
this(name, email, 0); // calls the 3-parameter constructor
}
}
// Usage
User u1 = new User(); // default
User u2 = new User("Alice", "a@b.com", 25); // parameterized
User u3 = new User("Bob", "b@b.com"); // chained