Package与Import

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我是靠谱客的博主贪玩荷花，这篇文章主要介绍Package与Import，现在分享给大家，希望可以做个参考。

– 定义一个圆类(Circle)，其所在的包为bzu.info.software；定义一个圆柱类Cylinder，其所在的包为bzu.info.com；定义一个主类A，其所在的包也为bzu.info.com，在A中生成一个Cylinder对象，并输出其体积。编译并运行该类

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package bzu.info.software;

public class Cricle {
    double radius;
    double area;
    Cricle(double r){
        radius=r;
    }
    double getArea(){
        area=3.14*radius*radius;
        return area;
    }

}

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package bzu.info.software;

public class Cylinder {
    Cricle bottom;//A类的变量成员是B类的对象
    double height;
    double volumn;
    Cylinder(Cricle c,double h){//A类中某个方法的参数是B类的对象
        bottom=c;
        height=h;
    }
    double getVolumn(){
        volumn=bottom.getArea()*height;
        return volumn;
    }

}

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package bzu.info.software;

public class A {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Cricle cr=new Cricle(2.0);
        Cylinder cy=new Cylinder(cr,5.0);       
        System.out.println(cy.getVolumn());

    }

}

这里写图片描述

改变所在包的位置

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package bzu.info.software;

public class Cricle {
    double radius;
    double area;
    public Cricle(double r){
        radius=r;
    }
    public double getArea(){
        area=3.14*radius*radius;
        return area;
    }

}

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package bzu.info.com;
import bzu.info.software.*;
public class Cylinder {
    Cricle bottom;
    double height;
    double volume;
    public Cylinder(Cricle c,double h){//A类中某个方法的参数是B类的对象
        bottom=c;
        height=h;
    }
    public double getVolume(){
        volume=bottom.getArea()* height;
        return volume;
    }

}

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package bzu.info.com;
import bzu.info.software.*;
public class A {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Cricle cr=new Cricle(2.0);
        Cylinder cy=new Cylinder(cr,5.0);               
        System.out.println(cy.getVolume());


    }

}