// --------------------------- Job ---------------------
type Job interface {
	Do()
}

type JobQueue chan Job
// --------------------------- Worker ---------------------
type Worker struct {
	JobChan JobQueue //每一個(gè)worker對(duì)象具有JobQueue（隊(duì)列）屬性。
}

// --------------------------- WorkerPool ---------------------
type WorkerPool struct { //線程池：
	Workerlen   int //線程池的大小
	JobQueue    JobQueue //Job隊(duì)列，接收外部的數(shù)據(jù)
	WorkerQueue chan JobQueue //worker隊(duì)列：處理任務(wù)的Go程隊(duì)列
}

package main

import (
	"fmt"
	"runtime"
	"time"
)

//定義一個(gè)實(shí)現(xiàn)Job接口的數(shù)據(jù)
type Score struct {
	Num int
}
//定義對(duì)數(shù)據(jù)的處理
func (s *Score) Do() {
	fmt.Println("num:", s.Num)
	time.Sleep(500*time.Millisecond) //模擬執(zhí)行的耗時(shí)任務(wù)
}

func main() {
	num := 100 * 100 * 2 //開啟 2萬個(gè)線程
	// debug.SetMaxThreads(num + 1000) //設(shè)置最大線程數(shù)
	// 注冊(cè)工作池，傳入任務(wù)
	// 參數(shù)1 worker并發(fā)個(gè)數(shù)
	p := NewWorkerPool(num)
	p.Run()

	//寫入一千萬條數(shù)據(jù)
	dataNum := 100 * 100* 100* 10
	go func() {
		for i := 1; i <= dataNum; i++ {
			sc := &Score{Num: i}
			p.JobQueue <- sc //數(shù)據(jù)傳進(jìn)去會(huì)被自動(dòng)執(zhí)行Do()方法，具體對(duì)數(shù)據(jù)的處理自己在Do()方法中定義
		}
	}()
	//循環(huán)打印輸出當(dāng)前進(jìn)程的Goroutine 個(gè)數(shù)
	for {
		fmt.Println("runtime.NumGoroutine() :", runtime.NumGoroutine())
		time.Sleep(5 * time.Second)
	}

}
// --------------------------- Job ---------------------
type Job interface {
	Do()
}
type JobQueue chan Job
// --------------------------- Worker ---------------------
type Worker struct {
	JobChan JobQueue //每一個(gè)worker對(duì)象具有JobQueue（隊(duì)列）屬性。
}

func NewWorker() Worker {
	return Worker{JobChan: make(chan Job)}
}
//啟動(dòng)參與程序運(yùn)行的Go程數(shù)量
func (w Worker) Run(wq chan JobQueue) {
	go func() {
		for {
		    wq <- w.JobChan //處理任務(wù)的Go程隊(duì)列數(shù)量有限，每運(yùn)行1個(gè)，向隊(duì)列中添加1個(gè)，隊(duì)列剩余數(shù)量少1個(gè) (JobChain入隊(duì)列)
			select {
			case job := <-w.JobChan:
				//fmt.Println("xxx2:",w.JobChan)
				job.Do() //執(zhí)行操作
			}
		}
	}()
}

// --------------------------- WorkerPool ---------------------
type WorkerPool struct { //線程池：
	Workerlen   int //線程池的大小
	JobQueue    JobQueue //Job隊(duì)列，接收外部的數(shù)據(jù)
	WorkerQueue chan JobQueue //worker隊(duì)列：處理任務(wù)的Go程隊(duì)列
}

func NewWorkerPool(workerlen int) *WorkerPool {
	return &WorkerPool{
		Workerlen:   workerlen,
		JobQueue:    make(JobQueue),
		WorkerQueue: make(chan JobQueue, workerlen),
	}
}
func (wp *WorkerPool) Run() {
	fmt.Println("初始化worker")
	//初始化worker(多個(gè)Go程)
	for i := 0; i < wp.Workerlen; i++ {
		worker := NewWorker()
		worker.Run(wp.WorkerQueue) //開啟每一個(gè)Go程
	}
	// 循環(huán)獲取可用的worker,往worker中寫job
	go func() {
		for {
			select {
			//將JobQueue中的數(shù)據(jù)存入WorkerQueue
			case job := <-wp.JobQueue: //線程池中有需要待處理的任務(wù)(數(shù)據(jù)來自于請(qǐng)求的任務(wù)) :讀取JobQueue中的內(nèi)容
				worker := <-wp.WorkerQueue //隊(duì)列中有空閑的Go程   ：讀取WorkerQueue中的內(nèi)容,類型為：JobQueue
				worker <- job //空閑的Go程執(zhí)行任務(wù)  ：整個(gè)job入隊(duì)列（channel） 類型為：傳遞的參數(shù)（Score結(jié)構(gòu)體）
				//fmt.Println("xxx1:",worker)
				//fmt.Printf("====%T  ;  %T======\n",job,worker,)
			}
		}
	}()
}

select {
			case job := <-wp.JobQueue: 
				worker := <-wp.WorkerQueue 
				worker <- job 
			
			}

worker <- job ：向worker中寫數(shù)據(jù)；

job := <-w.JobChan: 從w.JobChan中讀數(shù)據(jù)。