/**
    對象數(shù)組與管理
    使用對象數(shù)組實(shí)現(xiàn)多個(gè)Chicken的管理
    動(dòng)態(tài)數(shù)組：
    1.數(shù)組是一種線性數(shù)據(jù)結(jié)構(gòu)
    2.數(shù)組不適合做刪除插入等操作乐导，適合添加，查找抵蚊，遍歷等操作
*/
import java.util.Arrays;
public class TestChicken{
    public static void main(String[]args){
        ChickenManager cm = new ChickenManager(5);
        //添加
        cm.add(new Chicken(1,"小小",10));
        cm.add(new Chicken(2,"小二",8));
        cm.add(new Chicken(3,"小三",6));
        cm.add(new Chicken(4,"小紅",2));
        cm.add(new Chicken(5,"小奮",4));
        
        cm.add(new Chicken(6,"小斗",1));
        System.out.println("數(shù)組的長度是"+cm.length());
        
        System.out.println("...........printAll..........");
        cm.printAll();
        
        System.out.println("...........find..........");
        Chicken c = cm.find(6);
        c.print();
        
        System.out.println("...........update.........");
        cm.update(new Chicken(1,"鐵公雞",20));
        cm.printAll();
    }
}

//小雞管理類
class ChickenManager{
    
    private Chicken[] cs = null;
    private int count = 0;//記錄當(dāng)前數(shù)組元素個(gè)數(shù)（下標(biāo)）
    //構(gòu)造方法
    public ChickenManager(int size){
        if(size>0){
            cs = new Chicken[size];
        }else{
            cs = new Chicken[5];
        }
    }
    public int length(){
        return cs.length;
    }
    //添加:實(shí)現(xiàn)動(dòng)態(tài)數(shù)組
    public void add(Chicken c){
        if(count>=cs.length){//數(shù)組已滿躏升，需要擴(kuò)充
            //算法1:擴(kuò)充原來數(shù)組大小的一半左右 cs.length *3/2 + 1
            //算法2：擴(kuò)充原來數(shù)組的一倍  cs.length*2
            int newLen = cs.length*2;
            cs = Arrays.copyOf(cs,newLen);  
        }
        cs[count] = c;
        count++;
    }
    
    //刪除
    public void delete(int id){
        for(int i=0;i<count;i++){
            if(cs[i].getId()==id){
                //找到了要?jiǎng)h除的對象，把該對象之后的對象向前移動(dòng)一位
                for(int j=i;j<count-1;j++){
                    cs[j]=cs[j+1];
                }
                //把最后一個(gè)對象賦值為空（刪除）
                cs[count-1]=null;
                count-- ;//下標(biāo)減一
                break;
            }
        }
    }
    
    //更新
    public void update(Chicken c){
        Chicken temp = find(c.getId());
        if(temp!=null){
            temp.setName(c.getName());
            temp.setAge(c.getAge());
        }
    }
    
    //查找
    public Chicken find(int id){
        for(int i=0;i<count;i++){
            if(cs[i].getId()==id){
                return cs[i];
            }
        }
        return null;
    }
    
    //輸出所有
    public void printAll(){
        for(int i=0;i<count;i++){
            cs[i].print();
        }
    }
}


//小雞類（數(shù)據(jù)對象）value object(vo)
class Chicken{
    private int id;
    private String name;
    private int age;
    public Chicken(){}//一般情況下最好保留默認(rèn)的構(gòu)造方法
    public Chicken(int id,String name,int age){
        this.id = id;
        this.name = name;
        this.age = age;
    }
    public void setId(int id){
        this.id = id;
    }public int getId(){
        return id;
    }
    public void setName(String name){
        this.name = name;
    }
    public String getName(){
        return name;
    }
    public void setAge(int age){
        this.age=age;
    }
    public int getAge(){
        return age;
    }
    public void print(){
        System.out.println("id="+id+",name="+name+",age="+age);
    }
    
}

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