备忘录模式简介及Java实现示例

// 备忘录类

public class Memento {

private String state;

public Memento(String state) {

this.state = state;

}

public String getState() {

return state;

}

}

// 原发器类

public class Originator {

private String state;

public void setState(String state) {

this.state = state;

}

public String getState() {

return state;

}

public Memento saveStateToMemento() {

return new Memento(state);

}

public void getStateFromMemento(Memento memento) {

state = memento.getState();

}

}

// 管理者类

public class Caretaker {

private List mementoList = new ArrayList<>();

public void add(Memento state) {

mementoList.add(state);

}

public Memento get(int index) {

return mementoList.get(index);

}

}