package com.test;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

/**

 * @author tzq

 * @date 2019-03-13 16:48

 */

public class Test {

    //公共变量

    int count=0;

    static  List<Integer> list = new ArrayList<>();

    public static void main(String[] args) throws  Exception{

        //new一个实现Runnable的类

        Test test=new Test();

        //创建1个任务

        MyRunnable myRunnable1=test.new MyRunnable();

        //创建5个线程

        for(int i=0;i<99;i++){

            Thread t = new Thread(myRunnable1);

            t.start();

            t.join();

        }

        System.out.println("线程结束");

        System.out.println(list.size());

        long s1=System.nanoTime();

        for (Integer i :list){

        }

        System.out.println("foreach程序耗时："+(System.nanoTime()-s1)+" ms");

        long s2=System.nanoTime();

        Iterator iter = list.iterator();

        while(iter.hasNext()){

            Object o = iter.next();

        }

        System.out.println("Iterator程序耗时："+(System.nanoTime()-s2)+" ms");

        long s3=System.nanoTime();

        int size = list.size();

        for(int i=0;i<size;i++){

            Object o= list.get(i);

        }

        System.out.println("for程序耗时："+(System.nanoTime()-s3)+" ms");

        long s4=System.nanoTime();

        for(int i=0;i<list.size();i++){

            Object o= list.get(i);

        }

        System.out.println("for程序耗时："+(System.nanoTime()-s4)+" ms");

        long s5=System.nanoTime();

        list.stream().forEach(x->{

            Object o= x;

        });

        System.out.println("stream程序耗时："+(System.nanoTime()-s5)+" ms");

    }

    //创建一个实现Runnable的类

    class MyRunnable implements Runnable{

        public void run() {

            while(true){

                //锁住的是同一对象

                synchronized(this){

                    if(count>=1000000){

                        break;

                    }

                    list.add(count);

                    System.out.println(Thread.currentThread().getName()+":count:"+(++count));

                    //测试时，线程更容易切换

                    Thread.yield();

                }

            }

        }

    }

}