我從gobyexample做了一些編輯：import ( "fmt" "math/rand" "time")type DemoResult struct { Name string Rate int}func random(min, max int) int { rand.Seed(time.Now().UTC().UnixNano()) return rand.Intn(max-min) + min}func worker(id int, jobs <-chan int, results chan<- DemoResult) { for j := range jobs { fmt.Println("worker", id, "started job", j) time.Sleep(time.Second) fmt.Println("worker", id, "finished job", j) myrand := random(1, 4) if myrand == 2 { results <- DemoResult{Name: "succ", Rate: j} } // else { // results <- DemoResult{Name: "failed", Rate: 999} // } }}func main() { const numJobs = 5 jobs := make(chan int, numJobs) results := make(chan DemoResult) for w := 1; w <= 3; w++ { go worker(w, jobs, results) } for j := 1; j <= numJobs; j++ { jobs <- j } close(jobs) for a := 1; a <= numJobs; a++ { out := <-results if out.Name == "succ" { fmt.Printf("%v\n", out) } }}我評論了以下代碼，故意讓它永遠卡?。?nbsp; // else { // results <- DemoResult{Name: "failed", Rate: 999} // }看起來我們應該使結果的長度與作業的長度相同。我想知道我們是否可以讓它有不同的長度？
2 回答
牧羊人nacy
TA貢獻1862條經驗 獲得超7個贊
使用等待組來檢測工作人員何時完成。工作人員完成后關閉結果通道。接收結果直到通道關閉。
func worker(wg *sync.WaitGroup, id int,
jobs <-chan int,
results chan<- DemoResult) {
// Decrement wait group counter on return from
// function.
defer wg.Done()
?
}
func main() {
?
// Declare wait group and increment counter for
// each worker.
var wg sync.WaitGroup
for w := 1; w <= 3; w++ {
wg.Add(1)
go worker(&wg, w, jobs, results)
}
?
// Wait for workers to decrement wait group
// counter to zero and close channel.
// Execute in goroutine so we can continue on
// to receiving values from results in main.
go func() {
wg.Wait()
close(results)
}()
?
// Loop until results is closed.
for out := range results {
?
}
}
https://go.dev/play/p/FOQwybMl7tM
慕虎7371278
TA貢獻1802條經驗 獲得超4個贊
我想知道我們是否可以讓它有不同的長度？
絕對可以，但是您需要某種方法來確定何時到達結果的末尾。這就是您的示例失敗的原因 - 目前該函數假設會有numJobs（每個作業一個結果）結果并等待那么多。
另一種方法是使用通道關閉來指示這一點，即（游樂場）
package main
import (
"fmt"
"math/rand"
"sync"
"time"
)
type DemoResult struct {
Name string
Rate int
}
func random(min, max int) int {
rand.Seed(time.Now().UTC().UnixNano())
return rand.Intn(max-min) + min
}
func worker(id int, jobs <-chan int, results chan<- DemoResult) {
for j := range jobs {
fmt.Println("worker", id, "started job", j)
time.Sleep(time.Second)
fmt.Println("worker", id, "finished job", j)
myrand := random(1, 4)
if myrand == 2 {
results <- DemoResult{Name: "succ", Rate: j}
} // else {
// results <- DemoResult{Name: "failed", Rate: 999}
//}
}
}
func main() {
const numWorkers = 3
const numJobs = 5
jobs := make(chan int, numJobs)
results := make(chan DemoResult)
var wg sync.WaitGroup
wg.Add(numWorkers)
for w := 1; w <= numWorkers; w++ {
go func() {
worker(w, jobs, results)
wg.Done()
}()
}
go func() {
wg.Wait() // Wait for go routines to complete then close results channel
close(results)
}()
for j := 1; j <= numJobs; j++ {
jobs <- j
}
close(jobs)
for out := range results {
if out.Name == "succ" {
fmt.Printf("%v\n", out)
}
}
}
- 2 回答
- 0 關注
- 90 瀏覽
添加回答
舉報
0/150
提交
取消