Arguments

If you declare a constructor which takes arguments, you can use those arguments to give initial values to fields.¹

You need to pass the arguments in the () in the new expression, just like any other method invocation.

class Muppet {
    String name;

    Muppet(String name) {
        this.name = name;
    }
}

void main() {
    Muppet gonzo = new Muppet("Gonzo");

    // "Gonzo"
    System.out.println(gonzo.name);
}

When you declare a constructor that takes arguments, the default constructor will no longer be available.

class Muppet {
    String name;

    Muppet(String name) {
        this.name = name;
    }
}

void main() {
    // Need to provide a name now
    Muppet gonzo = new Muppet();
}