java设计模式进阶_memento

//////  Generated by StarUML(tm) Java Add-In////  @ Project : Untitled//  @ File Name : StarMemento.java//  @ Date : 2016/8/30//  @ Author : ////public interface StarMemento {}//////  Generated by StarUML(tm) Java Add-In////  @ Project : Untitled//  @ File Name : StarMementoInternal.java//  @ Date : 2016/8/30//  @ Author : ////public class StarMementoInternal implements StarMemento {    private StarType type;    private int ageYears;    private int massTons;    public StarType getType() {        return type;    }    public void setType(StarType type) {        this.type = type;    }    public int getAgeYears() {        return ageYears;    }    public void setAgeYears(int year) {        this.ageYears = year;    }    public int getMassTons() {        return massTons;    }    public void setMassTons(int massTons) {        this.massTons = massTons;    }}//////  Generated by StarUML(tm) Java Add-In////  @ Project : Untitled//  @ File Name : Star.java//  @ Date : 2016/8/30//  @ Author : ////public class Star {    private StarType type;    private int ageYears;    private int massTons;    public Star(StarType type, int startAge, int startMass) {        this.type = type;        this.ageYears = startAge;        this.massTons = startMass;    }    public void timePasses() {        ageYears *= 2;        massTons *= 8;        switch(type)        {        case RED_GIANT:            type = StarType.WHITE_DWARF;            break;        case SUN:            type = StarType.RED_GIANT;            break;        case SUPERNOVA:            type = StarType.DEAD;            break;        case WHITE_DWARF:            type = StarType.SUPERNOVA;            break;        case DEAD:            ageYears *= 2;            massTons = 0;            break;        default:            break;        }    }    public StarMemento getMemento() {        StarMementoInternal state = new StarMementoInternal();        state.setAgeYears(ageYears);        state.setMassTons(massTons);        state.setType(type);        return state;    }    public void setMemento(StarMemento memento) {        StarMementoInternal state = (StarMementoInternal)memento;        this.type = state.getType();        this.ageYears = state.getAgeYears();        this.massTons = state.getMassTons();    }    public String toString() {        return String.format("%s age: %d years mass: %d tons", type.toString(),ageYears,massTons);    }}public enum StarType {    SUN("sun"),//太阳    RED_GIANT("red giant"),//巨人    WHITE_DWARF("white dwarf"),//白色-矮人    SUPERNOVA("supernova"),//超新星    DEAD("dead star"),//废星    UNDEFINED("")//未命名    ;    private String title;    StarType(String title){        this.title = title;    }    public String toString()    {        return title;    }}import java.util.Stack;public class App {    public static void main(String[] args) {        Stack<StarMemento> states = new Stack<>();        Star star = new Star(StarType.SUN,10000000,500000);        System.out.println(star);        states.add(star.getMemento());        star.timePasses();        System.out.println(star);        states.add(star.getMemento());        star.timePasses();        System.out.println(star);        states.add(star.getMemento());        star.timePasses();        System.out.println(star);        states.add(star.getMemento());        star.timePasses();        System.out.println(star);        while(states.size() > 0)        {            star.setMemento(states.pop());            System.out.println(star);        }    }}/*sun age: 10000000 years mass: 500000 tonsred giant age: 20000000 years mass: 4000000 tonswhite dwarf age: 40000000 years mass: 32000000 tonssupernova age: 80000000 years mass: 256000000 tonsdead star age: 160000000 years mass: 2048000000 tonssupernova age: 80000000 years mass: 256000000 tonswhite dwarf age: 40000000 years mass: 32000000 tonsred giant age: 20000000 years mass: 4000000 tonssun age: 10000000 years mass: 500000 tons*/