go 有缓冲channel示例

package main

//有缓冲通道实例，代码参考《go语言实战》
import (
"sync"
"math/rand"
"time"
"fmt"
)

const (
numberGoroutines=4
taskLoad=10
)

var wg sync.WaitGroup

func init(){
rand.Seed(time.Now().Unix())
}

func main(){
task:=make(chan string,taskLoad)
wg.Add(numberGoroutines)
for gr:=1;gr<=numberGoroutines;gr++{
//开启gr等待任务运行
go work(task,gr)
}
//模拟运行任务
for wk:=1;wk<=taskLoad;wk++{
task<-fmt.Sprintf("task %d",wk)
}
close(task)
wg.Wait()
}

func work(tasks chan string,tasknum int){
defer wg.Done()
for{
task,ok:=<-tasks
if !ok{
fmt.Printf("Worker: %d : Shutting Down\n", tasknum)
return
}
fmt.Printf("worker: %d:started %s\n",tasknum,task)
// 随机等一段时间来模拟工作 71
sleep := rand.Int63n(100)
time.Sleep(time.Duration(sleep) * time.Millisecond)
// 显示我们完成了工作 75
fmt.Printf("Worker: %d : Completed %s\n", tasknum, task)
}
}