模板方法模式

//模板方法模式
abstract class time{
    public final void getTime() {//不让复写
        long start = System.currentTimeMillis();

        runcode();

        long end = System.currentTimeMillis();
        System.out.println("毫秒" + (end - start));
    }

    public abstract void runcode();
}

class Elem extends time{
    public void runcode() {
        for (int i = 0; i < 1000; i++) {
            System.out.println(i);
        }
    }
}

public class CurrentTime {
    public static void main(String[] args) {
        // GetTime gt = new GetTime();
        Elem gt = new Elem();
        gt.getTime();
    }
}