add: waitgroup的几种用法

interface/example1/sensor/sensor.go

@@ -0,0 +1,12 @@
+package sensor
+
+type Sensor interface {
+	Add()
+	Delete()
+	Update()
+	Search()
+}
+
+func AddSensor(s Sensor) {
+	s.Add()
+}

interface/example1/sensor/sensorimpl/ftp.go

@@ -0,0 +1,30 @@
+package sensorimpl
+
+import (
+	"fmt"
+	"golanglearn/interface/example1/sensor"
+)
+
+type Ftp struct {
+	Name string
+}
+
+func (f *Ftp) Add() {
+	fmt.Println("ftp sensor", f.Name)
+}
+
+func (f *Ftp) Delete() {
+	panic("implement me")
+}
+
+func (f *Ftp) Update() {
+	panic("implement me")
+}
+
+func (f *Ftp) Search() {
+	panic("implement me")
+}
+
+func NewFtp(name string) sensor.Sensor {
+	return &Ftp{Name: name}
+}

interface/example1/sensor/sensorimpl/rtsp.go

@@ -0,0 +1,30 @@
+package sensorimpl
+
+import (
+	"fmt"
+	"golanglearn/interface/example1/sensor"
+)
+
+type Rtsp struct {
+	Name string
+}
+
+func (r *Rtsp) Add() {
+	fmt.Println("add sensor", r.Name)
+}
+
+func (r *Rtsp) Delete() {
+	panic("implement me")
+}
+
+func (r *Rtsp) Update() {
+	panic("implement me")
+}
+
+func (r *Rtsp) Search() {
+	panic("implement me")
+}
+
+func NewRtsp(name string) sensor.Sensor {
+	return &Rtsp{Name: name}
+}

interface/main.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"golanglearn/interface/example1/sensor"
+	"golanglearn/interface/example1/sensor/sensorimpl"
+)
+
+func main() {
+	rtsp1 := sensorimpl.NewRtsp("xxx")
+	sensor.AddSensor(rtsp1)
+	ftp1 := sensorimpl.NewFtp("ftp")
+	sensor.AddSensor(ftp1)
+}

waitgroup/example2/main.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"fmt"
+	"strconv"
+	"sync"
+	"time"
+)
+
+/*
+限制并发数量的用法
+*/
+func main() {
+	wg := sync.WaitGroup{}
+	// 最多允许的并发数量
+	limit := make(chan struct{}, 20)
+	for i := 0; i < 100; i++ {
+		wg.Add(1)
+		limit <- struct{}{}
+		go func(num int) {
+			defer func() {
+				<-limit
+				wg.Done()
+			}()
+			dosth(num)
+		}(i)
+	}
+	wg.Wait()
+}
+
+func dosth(i int) {
+	fmt.Println("do sth-->", strconv.Itoa(i))
+	// 模拟耗时1s
+	time.Sleep(time.Second)
+}

waitgroup/example2/readme.md

@@ -0,0 +1 @@
+> 用waitgroup限制并发数量的用法