匿名内部类的使用场景 计算方法使用了多少秒

interface Task {
void runTask();
}

public class TimeCountDemo {
public static void countTime(Task task) {
long start = System.currentTimeMillis();
task.runTask();
long end = System.currentTimeMillis();
double cost = (end - start) / 1000.0;
System.out.println("方法执行耗时：" + cost + " 秒");
}

public static void main(String[] args) {
countTime(new Task() {
@Override
public void runTask() {
long sum = 0;
for (int i = 0; i < 100000000; i++) {
sum += i;
}
System.out.println("循环计算完成，总和：" + sum);
}
});
}
}