java两个问题，求解。求解。求解

Question

1.Java中for-each循环为何能放入对象Computer com，不都是放 数据类型 变量（int x） 的吗？
2.打印结果不应该是（一句我打印了，一句cpu吗）呈现四对，8行。为何是我打印了，4行，然后才是CPU4行？求解

package com.newknowledge.object;

public class Computer {
    //成员变量
    private String cpu = "Intel";//处理器
    private String memory;//内存
    private String keyBoard;//键盘
    private String mainBoard;//主板

    //构造方法
    public Computer(){
        System.out.println("------Computer()-----");
        cpu = "AMD";
    }

  public Computer(String cpu,String memory,String keyBoard,String mainBoard){
        System.out.println("我打印了");
        this.cpu = cpu;
        this.mainBoard = mainBoard;
        this.keyBoard = keyBoard;
        this.memory = memory;
    }
    public void show(){
        System.out.println("cpu="+cpu+",memory="+memory+
                ",mainBoard="+mainBoard+",keyBoard"+keyBoard);
    }

    public static void main(String[] args) {
    }
}

package com.newknowledge.object;

import java.util.Arrays;

public class TestArray {
    public static void main(String[] args){
        Computer[] arr = new Computer[4];
        arr[0] = new Computer("AM","2G","达尔优","七彩虹");
        arr[1] = new Computer("AM","2G","达尔优","七彩虹");
        arr[2] = new Computer("AM","2G","达尔优","七彩虹");
        arr[3] = new Computer("AM","2G","达尔优","七彩虹");
       
        for(Computer com:arr){
            com.show();
        }
    }
}

Answer 1

1.for-each帮JAVA用户直接忽略下标的声明，用户可以直接遍历数组或者列表中的对象，也就是Computer，不需要考虑下标去声明int i
2.“我打印了”是在构造函数中，每次创建对象也就是new的时候就会打印。先创建了四个对象所以会先打印四次“我打印了”，然后在foreach中每个对象访问自己的show方法，打印四次cpu