class Car {
String licensePlate; // e.g. "New York 543 A23"
double speed; // in kilometers per hour
double maxSpeed; // in kilometers per hour
}
To instantiate an object in Java, use the keyword new
followed by a call to the class's constructor. Here's how you'd
create a new Car
variable called c
:
Car c;
c = new Car();
The first word, Car
, declares the type of the variable
c
. Classes are types and variables of a class type
need to be declared just like variables that are ints or doubles.
The equals sign is the assignment operator and new
is the construction operator.
Finally notice the Car()
method. The parentheses
tell you this is a method and not a data type like the
Car
on the left hand side of the assignment. This is a
constructor, a method that creates a new instance of a class.
You'll learn more about constructors shortly. However if you do
nothing, then the compiler inserts a default constructor that takes
no arguments.
This is often condensed into one line like this:
Car c = new Car();