State Pattern - Demo One - TV Remote

package StatePatternDemoOne;

public interface State {
    public void doAction();
}

package StatePatternDemoOne;

public class TVStartState implements State {
    @Override
    public void doAction() {
        System.out.println("TV is turned ON");
    }
}

package StatePatternDemoOne;

public class TVStopState implements State {
    @Override
    public void doAction() {
        System.out.println("TV is turned OFF");
    }
}

package StatePatternDemoOne;

    public class TVContextClass implements State {
        private State tvState;

        public void setState(State state) {
            this.tvState = state;
        }

        public State getState() {
            return this.tvState;
        }

        @Override
        public void doAction() {
            this.tvState.doAction();
        }
    }

package StatePatternDemoOne;

public class TVRemote {
    public static void main(String[] args) {
        TVContextClass context = new TVContextClass();
        State tvStartState = new TVStartState();
        State tvStopState = new TVStopState();

        context.setState(tvStartState);
        context.doAction();

        context.setState(tvStopState);
        context.doAction();
    }
}