Golang中的select使用

package main

import (
	"fmt"
	"time"
	"sync"
)

type resultData struct {
    Job int
    Result bool
}

func main() {
    n := 10
    jobs := make(chan int, n)
    result := make(chan resultData, n)

    var wg sync.WaitGroup
    wg.Add(n)
    go publishJob(jobs, n)
    go daemon(jobs, result, &wg)
    wg.Wait()
    fmt.Printf("finish %v jobs", n)
}

func publishJob(jobs chan int, n int)  {
    for i:=0;i<n ;i++{
        jobs <- i
        //time.Sleep(time.Duration(i) * time.Millisecond)
    }
}

func daemon(jobs chan int, result chan resultData, wg *sync.WaitGroup)  {
    for {
        select {
        case j := <- jobs :
            fmt.Printf("have jobs %v\n", j)
            r := resultData{Job:j, Result:true}
            result <- r
            time.Sleep(time.Millisecond * 3)
        case r := <- result :
            fmt.Printf("job = %v, result = %v\n", r.Job, r.Result)
            wg.Done()
        default :
            //fmt.Printf("in default \n")    
        }
    }
}

输出结果如下：

[Running] go run "/home/sky/go-dsp/src/test2/main.go"
have jobs 0
job = 0, result = true
have jobs 1
have jobs 2
have jobs 3
job = 1, result = true
job = 2, result = true
have jobs 4
have jobs 5
have jobs 6
job = 3, result = true
job = 4, result = true
have jobs 7
job = 5, result = true
job = 6, result = true
job = 7, result = true
have jobs 8
have jobs 9
job = 8, result = true
job = 9, result = true
finish 10 jobs
[Done] exited with code=0 in 0.142 seconds

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