Visitor Pattern

Posted 2020-12-13 nedrain

问题

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Solve

// Action.java
public abstract class Action {
    public abstract void getManResult(Man man);

    public abstract void getWomanResult(Woman woman);


}

// Success.java
public class Success extends Action {
    @Override
    public void getManResult(Man man) {
        System.out.println("Man said you‘re great.");
    }

    @Override
    public void getWomanResult(Woman woman) {
        System.out.println("Woman said you are great.");
    }
}

// Fail.java
public class Fail extends Action{
    @Override
    public void getManResult(Man man) {
        System.out.println("Man said you are a looser.");
    }

    @Override
    public void getWomanResult(Woman woman) {
        System.out.println("Woman said you‘re a looser.");
    }
}

// Person.java
public abstract class Person {
    public abstract void accept(Action action);
}

// Man.java
public class Man extends Person{
    @Override
    public void accept(Action action) {
        action.getManResult(this);
    }
}

//Woman.java
public class Woman extends Person {
    @Override
    public void accept(Action action) {
        action.getWomanResult(this);
    }
}

//ObjectStructure.java
import java.util.LinkedList;
import java.util.List;

public class ObjectStructure {
    private List<Person> personList = new LinkedList<Person>();

    public void attach(Person p){
        personList.add(p);
    }

    public void detach(Person p){
        personList.remove(p);
    }

    public void display(Action action){
        for(Person p : personList){
            p.accept(action);
        }
    }
}