概念:将类的某些信息隐藏在类内部,不允许外部程序直接访问,而是通过该类提供的方法来实现对隐藏信息的操作和访问
好处:
- 只能通过规定的方法访问数据
- 隐藏类的实例细节,方便修改和实现
package com.imooc;
public class Telphone {
private float screen;
private float cpu;
private float mem;
public Telphone(){
System.out.println("无参的构造函数执行了");
}
public Telphone(float newScreen,float newCpu,float newMem){
System.out.println("有参的构造函数执行了!");
if(newScreen<3.5){
System.out.println("输入尺寸错误,默认为3.5");
screen=3.5f;
}
else{
screen=newScreen;
}
cpu=newCpu;
mem=newMem;
}
public void setScreen(float newScreen){
screen=newScreen;
}
public float getScreen(){
System.out.println("screen="+screen);
return screen;
}
}
package com.imooc;
public class InitailTelphone {
public static void main(String[] args) {
// TODO Auto-generated method stub
Telphone phone=new Telphone();
//Telphone phone2=new Telphone(1.5f,2.0f,1.2f);
phone.setScreen(5.5f);
phone.getScreen();
}
}