Java-定义圆类
目录
Java-定义圆类01：
Java-定义圆类02：
组合----》圆类+点类
用点类的对象p，作为圆类的属性。
先定义点类：
圆类02：
圆类03
圆03：
圆怎么形成的？
点和半径
-----------------》》》》》》》
继承点类，创建圆。
点类（父类）
子类：
测试类：
运行结果：
Java-定义圆类01：
package Lian.Xi;
/**
* @author captain_dong
* --圆类定义：
* 属性：圆心坐标-半径---方法：计算周长-面积
*/
public class Yuan01 {
private double x;
private double y;
private double r;
//无参构造
public Yuan01() {
}
//有参构造
public Yuan01(double x, double y, double r) {
this.x = x;
this.y = y;
this.r = r;
}
public double getX() {
return x;
}
public void setX(double x) {
this.x = x;
}
public double getY() {
return y;
}
public void setY(double y) {
this.y = y;
}
public double getR() {
return r;
}
public void setR(double r) {
this.r = r;
}
//计算周长
public double Zc(){
return 2*Math.PI*this.r;
}
//计算面积
public double Area(){
return Math.PI*Math.pow(this.r,2);
}
//获取圆的信息
@Override
public String toString() {
return "Yuan01{" +
"横坐标：x=" + x +
",纵坐标：y=" + y +
", 半径r=" + r +
'}';
}
}
Java-定义圆类02：
组合----》圆类+点类
用点类的对象p，作为圆类的属性。
先定义点类：
package Lian.Xi;
public class Point {
private double x;
private double y;
public Point() {
}
public Point(double x, double y) {
this.x = x;
this.y = y;
}
public double getX() {
return x;
}
public void setX(double x) {
this.x = x;
}
public double getY() {
return y;
}
public void setY(double y) {
this.y = y;
}
@Override
public String toString() {
return "Point{" +
"x=" + x +
", y=" + y +
'}';
}
//获取点信息
public String getMessage(){
String PXx;
return PXx="该圆心的点的坐标为："+"("+this.x+","+this.y+")";
}
}
圆类02：
package Lian.Xi;
/**
* @author captain_dong
* --圆类定义02：
* 属性：圆心坐标-半径---方法：计算周长-面积
*/
public class Yuan02 {
private Point p;
private double r;
//无参构造
public Yuan02() {
}
//有参构造
public Yuan02(Point p, double r) {
this.p = p;
this.r = r;
}
//计算周长
public double Zc(){
return 2*Math.PI*this.r;
}
//计算面积
public double Area(){
return Math.PI*Math.pow(this.r,2);
}
//获取圆的信息
public String getYuan(){
String gy="";
//gy="("+p.getX()+","+p.getY()+")"+",半径："+this.r;
gy=p.getMessage()+",半径："+this.r;
return gy;
}
@Override
public String toString() {
return "Yuan02{" +
"p=" + p +
", r=" + r +
'}';
}
}
圆类03
圆03：
圆怎么形成的？
点和半径
-----------------》》》》》》》
继承点类，创建圆。
点类（父类）
package Lian.Xi;
public class Point {
private double x;
private double y;
public Point() {
}
public Point(double x, double y) {
this.x = x;
this.y = y;
}
public double getX() {
return x;
}
public void setX(double x) {
this.x = x;
}
public double getY() {
return y;
}
public void setY(double y) {
this.y = y;
}
@Override
public String toString() {
return "Point{" +
"x=" + x +
", y=" + y +
'}';
}
//获取点信息
public String getMessage(){
String PXx;
return PXx="该圆心的点的坐标为："+"("+this.x+","+this.y+")";
}
}
子类：
package Lian.Xi;
/**
* 继承点类，创建圆。
*/
public class Yuan03 extends Point{ //父类
//添加一个新属性
private double r;
public Yuan03(){
super();//父类对象
}
//子类（新类）构造方法
public Yuan03(double x,double y,double r){//3个属性
super(x,y);//点 x，y super（）：父类对象，--》使用父类对象构造方法，形成点对象
this.r=r;
}
//新的构造函数
public Yuan03(Point p,double r){//2个属性
super(p.getX(),p.getY());
this.r=r;
}
//添加新方法
//计算周长
public double Zc(){
return 2*Math.PI*this.r;
}
//计算面积
public double Area(){
return Math.PI*Math.pow(this.r,2);
}
//获取圆信息
public String getMessage(){ //修改功能
String YXx;
YXx="圆是："+super.getMessage()+",半径 r= "+this.r;
return YXx;
}
}
测试类：
package Lian.Xi;
public class TestYuan {
public static void main(String[] agrs){
Yuan01 yuan01=new Yuan01(10,-10,100);
Point point=new Point(20,-20);
Yuan02 yuan02=new Yuan02(point,100);
Yuan03 yuan03=new Yuan03(30,-30,100);
Yuan03 yuan031=new Yuan03(point,100);
System.out.println("Yuan01'Message is :"+yuan01.toString());
System.out.println("Yuan02'Message is :"+yuan02.getYuan());
System.out.println("Yuan03'Message is :"+yuan03.getMessage());
System.out.println("Yuan03-1'Message is :"+yuan031.getMessage());
}
}
运行结果：
