Re: Can a method be a parameter of another method in Java?
Shawn schrieb:
Ingo R. Homann wrote:
Of course it can, see below. A great advantage of Java is, that its
solution is also typesafe!
Ciao,
Ingo
interface Mapper {
int map(int d);
}
class Test {
double sum(Mapper m, int a, int b) {
int sum=0;
for(int i=a;i<=b;i++) {
sum+=m.map(i);
}
return sum;
}
void test() {
System.out.println(sum(
new Mapper(){public int map(int x) {return x*x;}},
5,10));
System.out.println(sum(
new Mapper(){public int map(int x) {return (x+50)*(x+50);}},
5,10));
// ...
}
}
Fantastic! Thank you very much. I didn't realize interface can be such a
use--place holder. I thought interface was only used in inheritance.
One more question about the "public" word:
interface Mapper {
int map(int d); //Did you forget "public" here?
}
No, Ingo didn't forget the public. A interface only have public methods
so the public keyword may be omitted.
Bye
Michael
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