封装D问题

package com.imooc;

public class Gouzao {

float screen;

float cpu;

float men;

public Gouzao(){

System.out.println("无参构造方法执行了");

}

    public Gouzao(float newScreen,float newCpu,float newMen){

    if(newScreen<3.5){

    System.out.println("您输入的参数有误，自动赋值为3.5");

    screen=3.5f;

    }else{

    screen=newScreen;

    }

    cpu=newCpu;

    men=newMen;

    System.out.println("有参的构造方法执行了"+screen+"\t"+cpu+"\t"+men);

    }

}

package com.imooc;

public class IntGouzao {

public static void main(String[] args) {

Gouzao phone=new Gouzao();

Gouzao phone1=new Gouzao(4.0f,4.0f,5.2f);

phone.cpu=3.6f;

phone1.screen=6.0f;

}

}

无参构造方法执行了

有参的构造方法执行了4.0 4.0 5.2

结果没有变，为什么？？