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[Java]_ch11.2_不同類別庫間存取

package Taipei;

public class CCircle{

protected double pi;

protected double radius;

public CCircle() {

System.out.println("0.父類別建構元()，pi="+pi+" radius="+radius);

}

public CCircle(double r) {

radius=r;

pi=3.14;

System.out.println("1.父類別建構元(double)，pi="+pi+" radius="+radius);

}

public CCircle(double p,double r) {

pi=p;

radius=r;

System.out.println("2.父類別建構元(double,double)，pi="+pi+" radius="+radius);

}

public final void show() {

System.out.println("父類別show()，area="+pi*radius*radius);

}

public void set(double p,double r) {

radius=r;

pi=p;

System.out.println("父類別set()，pi="+pi+" radius="+radius);

}

}

package Hsinchu;

public class CCoin extends Taipei.CCircle{

private int value;

public CCoin(){

value=5;

System.out.println("0.子類別建構元()，value="+value+" pi="+pi+" radius="+radius);

}

public CCoin(double v){

super(v);

value=(int) v;

System.out.println("1.子類別建構元(double)，value="+value+" pi="+pi+" radius="+radius);

}

public void setValue(int v) {

value=v;

System.out.println("子類別setValue(int)，value="+value);

}

// public void show() {

// System.out.println("子類別show()，area="+pi*radius*radius+"value="+value+" pi="+pi+" radius="+radius);

// }

public void showValue() {

System.out.println("子類別showValue()，value="+value);

}

public String toString() {

String msg="兒子改寫的toString(),pi="+pi+" radius="+radius+" value="+value;

return msg;

}

}

package Gjun;

public class A9 {

public static void main(String[] args) {

Taipei.CCircle c1=new Taipei.CCircle();

c1.set(3.14, 2.0);

c1.show();

Taipei.CCircle c2=new Taipei.CCircle(4.0);

// c2.setValue(200);

Hsinchu.CCoin c3=new Hsinchu.CCoin();

Hsinchu.CCoin c4=new Hsinchu.CCoin(100);

c4.set(6.28, 5.0);

c4.setValue(999);

c4.show();

c4.showValue();

Taipei.CCircle c5=new Hsinchu.CCoin();

Hsinchu.CCoin c6=(Hsinchu.CCoin) c5;

c5.show();

// c5.showValue();

System.out.println("c1.getClass()="+c1.getClass());

System.out.println("c3.getClass()="+c3.getClass());

System.out.println("c5.getClass()="+c5.getClass());

System.out.println("c5.equals(c6)="+c5.equals(c6));

System.out.println("c1.equals(c3)="+c1.equals(c3));

System.out.println("c6.toString()="+c6.toString());

System.out.println("c1.toString()="+c1.toString());

}

}