chapter08_03.java

适合于初学者使用的许多经典的实例

                                          // ---------------从某一构造函数内调用另一个构造函数-----------------

class C02_Circle {
	     private double pi=3.1415926;
	     private double radius;
	     private String color;
	     
	     public C02_Circle() {                               // 没有参数的构造函数
	     	 this("GREEN",4.0);                                 // 从没有参数的构造函数调用其它的有参数的构造函数
	  	   	 System.out.println("Constructor C01_Circle() called !");
	     }
	     
         public C02_Circle(String str,double r) {                   // 有参数的构造函数
             System.out.println("Constructor public C01_Circle() called !");
             color=str;
             radius=r;
         }
         
         public void show() {
         	 System.out.println("radius="+radius+", area="+pi*radius*radius);
         	 System.out.println("Color="+color+"\n");
         }
}

public class Chapter08_03 {
	     public static void main(String[] args) {
             C02_Circle cir=new C02_Circle();
             cir.show();
         }
}