利用钩子函数测试某段代码的执行效率

package com.callback;
/**
* main方法测试
* @author tiger
*
*/
public class CountTime {
public static void main(String[] args) {
Test test = new Test();
test.getTime();
}
}
/**
* 测试类
* @author tiger
*
*/
class Test extends GetTime{
@Override
public void userCode() {
for (int i = 0; i < 12000; i++) {
int a = i+i;
System.out.println(a);
//...code....
}
}
}
/**
* 运行时间封装抽象类
* @author tiger
*
*/
abstract class GetTime{
public final void getTime(){
long start=System.currentTimeMillis();	//1s=1000ms

userCode();//钩子、bushi回调

long stop=System.currentTimeMillis();
System.out.println("本程序共花费了："+(stop-start)+"毫秒");
}
public abstract void userCode();
}