Google资深工程师深度讲解Go语言-channel 通道 (十)

一.channel

• channel
• buffered channel
• range.由发送方结束发送
• 理论基础:communication sequential process(csp)
• 不要通过共享内存来通信;通过通信来共享内存

      package main
      import (
     	"fmt"
     	"time"
      )
      func chanDemo() {
      	c := make(chan int)
     	go func() {
     		for {
      			n := <-c
      			fmt.Println(n)
     			//Output:
     			// 1
     			//2
      		}
      	}()
      	c <- 1
      	c <- 2
      	time.Sleep(time.Microsecond)
      }
      func main() {
      	chanDemo()
      }
  
 

      package main
      import (
     	"fmt"
     	"time"
      )
      func worker(id int, c chan int) {
     	for n := range c {
     		//n := <-c //收数据
     		//n, ok := <-c
     		//if !ok {
     		// break
     		//}
      		fmt.Printf("worker %d received %d\n", id, n)
     		//fmt.Println(n)
     		//Output:
     		// 1
     		//2
      	}
      }
      func createWorker(id int, ) chan<- int { //返回channel
      	c := make(chan int)
     	go worker(id, c)
     	return c
      }
      func chanDemo() {
     	//var c chan int //变量c 是个chanel 里面内容是int
     	//c := make(chan int)
     	var channels [10]chan<- int
     	for i := 0; i < 10; i++ {
      		channels[i] = createWorker(i)
      	}
     	for i := 0; i < 10; i++ {
      		channels[i] <- 'a' + i
      	}
     	for i := 0; i < 10; i++ {
      		channels[i] <- 'A' + i
      	}
     	//c <- 1 //发数据
     	//c <- 2
      	time.Sleep(time.Microsecond)
      }
      func bufferedChannel() {
      	c := make(chan int, 3)
     	go worker(0, c)
      	c <- 'a'
      	c <- 'b'
      	c <- 'c'
      	c <- 'd'
      	time.Sleep(time.Microsecond)
      }
      func channelClose() { //发送方通知接收方
      	c := make(chan int, 3)
     	go worker(0, c)
      	c <- 'a'
      	c <- 'b'
      	c <- 'c'
      	c <- 'd'
     	close(c)
      	time.Sleep(time.Microsecond)
      }
      func main() {
      	fmt.Println("channel ad first-class citizen")
      	chanDemo()
      	fmt.Println("Buffered channel")
      	bufferedChannel()
      	fmt.Println("Channel close and range")
      	channelClose()
      }
  
 

二.传统同步机制

• waitGroup :等待组
• Mutex 互斥
• Cond

      package main
      import (
     	"fmt"
     	"sync"
     	"time"
      )
      type atomicInt struct {
      	value int
      	lock sync.Mutex
      }
      func (a *atomicInt)increment()  {
      	a.lock.Lock()
     	defer a.lock.Unlock()
      	a.value++
      }
      func (a *atomicInt)get()int  {
      	a.lock.Lock()
     	defer a.lock.Unlock()
     	return a.value
      }
      func main() {
     	var a atomicInt
      	a.increment()
     	go func() {
      		a.increment()
      	}()
      	time.Sleep(time.Second)
      	fmt.Println(a.get())
      }
  
 

文章来源: blog.csdn.net，作者：lxw1844912514，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/lxw1844912514/article/details/108448296