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| abstract class State {
void doWork() {
}
}
class Happy extends State {
@Override
void doWork() {
System.out.println("happy");
}
}
class Sad extends State {
@Override
void doWork() {
System.out.println("sad");
}
}
class Context {
private State state;
public void setState(State state) {
this.state = state;
}
public void work() {
state.doWork();
}
}
public class StatePatternDemo {
public static void main(String[] args) {
Context context = new Context();
context.setState(new Happy());
context.work();
context.setState(new Sad());
context.work();
}
}
|