43 lines
657 B
Go
43 lines
657 B
Go
package main
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import "sync"
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//某些操作只需要在高并发场景中做一次，例如加载配置文件
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//这种场景下用到sync.once
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var waitGroup sync.WaitGroup
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var once sync.Once
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func send(ch1 chan<- int) {
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defer waitGroup.Done()
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for i := 0; i < 100; i++ {
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ch1 <- i
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}
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close(ch1)
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}
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func getV(ch1 <-chan int, ch2 chan<- int) {
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defer waitGroup.Done()
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for {
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x, ok := <-ch1
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if !ok {
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break
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}
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ch2 <- x * x
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}
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once.Do(func() { close(ch2) })
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}
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func main() {
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a := make(chan int, 100)
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b := make(chan int, 100)
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waitGroup.Add(3)
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go send(a)
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go getV(a, b)
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go getV(a, b)
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waitGroup.Wait()
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for ret := range b {
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println(ret)
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}
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}
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