[Java速成]3. Java面向对象编程，

JAVA面向对象编程

1. 封装特性:

一般情况下在一个包中定义类，一个类一个.java文件：

// Telephone.java
package com.functionD;

public class Telephone {

    static String brand;
    float screen;
    float cpu;
    float mem;

    //初始化代码块
    {
        screen = 9.7f;
        cpu = 2.5f;
        mem = 4.0f;
    }

    static {
        brand = "apple";
    }

    // 构造方法
    public Telephone(){
        System.out.println("Telephone has be created by no parameter!");
    }

    public Telephone(float screenIn, float cpuIn, float memIn){
        screen = screenIn;
        cpu = cpuIn;
        mem = menIn;
        System.out.println("Telephone has be created by parameters!");
    }

    void call (){
        System.out.println("Telephone call!");
    }

    void sendMassage() {
        System.out.println("Telephone sendMassage!");
    }
}

2. 继承特性

3. 多态特性