A concrete class is complete. Because all of its methods are implemented, we call it a concrete class, and we can instantiate it: Car car = new Car(); Some examples of concrete classes from the JDK are HashMap, HashSet, ArrayList, and LinkedList .
A concrete class is complete. Because all of its methods are implemented, we call it a concrete class, and we can instantiate it: Car car = new Car(); Some examples of concrete classes from the JDK are HashMap, HashSet, ArrayList, and LinkedList .