package com.main;

import cn.hutool.core.date.DateUtil;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Test {




    public static void main(String[] args) {
        ExecutorService executorService = Executors.newSingleThreadExecutor();

        long now = DateUtil.current(true);

        System.out.println("开始执行时间：" +  now);

        executorService.submit(Test::loopHello);

        long now2 = DateUtil.current(true);
        System.out.println("结束执行时间：" +  now2);
        System.out.println("总执行时间：" + (now2 - now));

    }

    private static void loopHello() {
        var i=0;
        while (i< 1000000000) {
            i++;
            sayHello();
        }
    }

    private static Integer sayHello() {
        var b = 1;
        var a = 22;
        return a + b;
    }

}


开始执行时间：264803974827800
结束执行时间：264804026950899
总执行时间：52123099

package main

import (
    "fmt"
    "time"
)

func sayHello() int {
    b := 1
    a := 22
    c := a + b
    return c
}

func loopHello() {
    var i=0
    for i<1000000000 {
        i++
        sayHello()
    }
}

func main() {
    nanosecond := time.Now().Nanosecond()
    fmt.Println("开始执行时间:", nanosecond)

    go loopHello()

    i2 := time.Now().Nanosecond()

    fmt.Println("结束执行时间:", i2)

    fmt.Println("总执行时间:", i2 - nanosecond)


}

开始执行时间: 558146100
结束执行时间: 558146100
总执行时间: 0