Question

大家帮我看看，这个内部类程序，到底哪里有错误，谢谢！JAVA

class Cubic
{double getCubic(int n)
{return 0;
}
}
abstract class Sqrt
{public abstract double getSqrt(int x);
}
class A
{void f(Cubic cubic)
{double result=cubic.getCubic(3);
System.out.println(result);
}
}
public class Example4_31
{public static void main (String args[])
{A a=new A();
a.f(new Cubic()
{double getCubic(int n)
{return n*n*n;
}
}
};
Sqrt ss=new Sqrt()
{public double getSqrt(int x)
{return Math.sqrt(x);
}
};
double m=ss.getSqrt(5);
System.out.println(m);
}
}

Answer 1

class Cubic {
double getCubic(int n){
return 0;
}
}
abstract class Sqrt {
public abstract double getSqrt(int x);
}
class A {
void f(Cubic cubic) {
double result=cubic.getCubic(3);
System.out.println(result);
}
}
public class Example4_31 {
public static void main (String args[]) {
A a=new A();
a.f(new Cubic(){
double getCubic(int n) {
return n*n*n;
}
} ); //加右括号
Sqrt ss=new Sqrt() {
public double getSqrt(int x)
{return Math.sqrt(x); } };
double m=ss.getSqrt(5);
System.out.println(m);
}
}