1.一對多

class Person{
    private String name;
    private String phone;
    private Car[] cars;
    public Person(){}
    public Person(String name,String phone){
        this.name = name;
        this.phone = phone;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        
 
this.name = name;
    }
    public String getPhone(){
        return phone;
    }
    public void setPhone(String phone){
        this.phone = phone;
    }
    public Car[] getCars(){
        return cars;
    }
    public void setCars(Car[] cars){
        this.cars = cars;
    }
    public String getInfo(){
        
 
return "姓名："+name+"，電話："+phone;
    }
}
class Car{
    private String brand;
    private String color;
    private Person person;
    public Car(){}
    public Car(String brand,String color){
        this.brand = brand;
        this.color = color;
    }
    public String getBrand(){
        return brand;
    }
    
 
public void setPhand(String brand){
        this.brand = brand;
    }
    public String getColor(){
        return color;
    }
    public void setColor(String color){
        this.color = color;
    }
    public Person getPerson(){
        return person;
    }
    public void setPerson(Person person){
        this.person = person;
    }
    public String getInfo(){
        return "品牌："+brand+"，顏色："+color;
    }
}

class Lei{
    public static void main(String[] args){    
        Person p1 = new Person("李三","05333-6543887");
        Person p2 = new Person("趙四","05333-6543000");
        Car c1 = new Car("奧迪","白色");
        Car c2 = new Car("大眾","黑色");
        Car c3 = new Car("吉利","紅色");
        p1.setCars(new Car[]{c1,c2});
        p2.setCars(new Car[]{c3});
        c1.setPerson(p1);
        c2.setPerson(p1);
        c3.setPerson(p2);
        System.out.println(p1.getInfo()+"， 所擁有的汽車及汽車顏色：");
        
        for(int i = 0;i < p1.getCars().length;i++){
            System.out.println(p1.getCars()[i].getInfo());
        }
        
        System.out.println(c1.getPerson().getInfo());

    }
}

2.多對多

class Shop
{
    private String name;
    private String city;
    private Goods[] goods;
    public Shop(){}
    public Shop(String name,String city){
        this.name = name;
        this.city = city;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
    public String getCity(){
        return city;
    }
    public void setCity(String city){
     this.city = city;
    }
    public Goods[] getGoods(){
        return goods;
    }
    public void setGoods(Goods[] goods){
        this.goods = goods;
    }
    public String getInfo(){
        return "商場:"+name+", 區域："+city;
    }
}
class Goods
{
    private String name;
    private double price;
    private Shop[] shops;
    public Goods(){}
    public Goods(String name,double price){
        this.name = name;
        this.price = price;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
    public double getPrice(){
        return price;
    }
    public void setPrice(double price){
        this.price = price;
    }
    public Shop[] getShop(){
        return shops;
    }
    public void setShop(Shop[] shops){
        this.shops = shops;
    }
    public String getInfo(){
        return "商品名："+name+"，價格："+price;
    }
}
class  Zio
{
    public static void main(String[] args) 
    {
        Shop s1 = new Shop("家樂福","青島");
        Shop s2 = new Shop("大潤發","淄博");
        Shop s3 = new Shop("家家樂","日照");

        Goods g1 = new Goods("襯衣",189.5);
        Goods g2 = new Goods("紅酒",489.99);
        Goods g3 = new Goods("匯源飲料",12.0);
        
         //一個商場可以售賣多種商品
        s1.setGoods(new Goods[]{g1,g2,g3});
        s2.setGoods(new Goods[]{g2,g3});
        s3.setGoods(new Goods[]{g1,g3});
        
         //一種商品可以在多個商場售賣
        g1.setShop(new Shop[]{s1,s3});
        g2.setShop(new Shop[]{s1,s2});
        g3.setShop(new Shop[]{s1,s2,s3});
         
        System.out.println(s1.getInfo() +"所售商品及價格："); //s1對象調用getInfo()方法
        for(int i = 0;i < s1.getGoods().length;i++){ //數組遍歷
            System.out.println(s1.getGoods()[i].getInfo());
        }
        System.out.println();
        System.out.println(g3.getInfo()+"所在商場及城市："); //g3對象調用getInfo()方法
        for(int i = 0;i < g3.getShop().length;i++){ //數組遍歷
            System.out.println(g3.getShop()[i].getInfo());
        }
    }
}

java類一對多，多對多