feat(go): 添加反射和通道相关功能

- 新增 main31 和 main32 函数入口
- 实现接口实现检查函数 checkImplementation
- 添加结构体包装器 Wrapper 及其字段反射方法 getUnderlying- 实现通道类型检查与数据发送功能
- 添加通道选择器 readChannels 支持多通道读取
- 创建测试函数 testChannelRead 和 testChannelRead1 验证通道操作

27-reflection/reflection/main.go

@@ -29,4 +29,6 @@ func main() {
 	main28()
 	main29()
 	main30()
+	main31()
+	main32()
 }

27-reflection/reflection/re3.go

@@ -198,6 +198,7 @@ func executeFirstVoidMethod1(s interface{}) {
 		}
 	}
 }
+
 func main30() {
 	Printfln("\nmain30:")
 
@@ -210,3 +211,166 @@ func main30() {
 	executeFirstVoidMethod(&Product{Name: "Kayak", Price: 279})
 	executeFirstVoidMethod1(&Product{Name: "Kayak", Price: 279})
 }
+
+func checkImplementation(check interface{}, targets ...interface{}) {
+	checkType := reflect.TypeOf(check)
+	if checkType.Kind() == reflect.Ptr && checkType.Elem().Kind() == reflect.Interface {
+		checkType = checkType.Elem()
+		for _, target := range targets {
+			targetType := reflect.TypeOf(target)
+			Printfln("Type: %v implements %v : %v", targetType, checkType, targetType.Implements(checkType))
+		}
+	}
+}
+
+type Wrapper struct {
+	NamedItem
+}
+
+// 获取接口定义字段的实现类
+func getUnderlying(item Wrapper, fieldName string) {
+	itemVal := reflect.ValueOf(item)
+	fieldVal := itemVal.FieldByName(fieldName)
+	fieldType := fieldVal.Type()
+	Printfln("Field Type: %v ", fieldType)
+
+	for i := 0; i < fieldType.NumMethod(); i++ {
+		method := fieldType.Method(i)
+		Printfln("Interface Method: %v, PkgPath: %v, ", method.Name, method.PkgPath)
+	}
+
+	Printfln("-----------")
+	if fieldVal.Kind() == reflect.Interface {
+		fieldElem := fieldVal.Elem()
+		fieldElemType := fieldElem.Type()
+		Printfln("Underlying Type: %v", fieldElemType)
+
+		for i := 0; i < fieldElemType.NumMethod(); i++ {
+			method := fieldElemType.Method(i)
+			Printfln("Underlying Method: %v, PkgPath: %v, ", method.Name, method.PkgPath)
+		}
+	}
+}
+
+func main31() {
+	Printfln("\nmain31:")
+
+	currencyItemType := (*CurrencyItem)(nil)
+	checkImplementation(currencyItemType, Product{}, &Product{}, &Purchase{})
+
+	getUnderlying(Wrapper{NamedItem: &Product{}}, "NamedItem")
+}
+
+func inspectChannel(channel interface{}) {
+	Printfln("\ninspectChannel:")
+	channelType := reflect.TypeOf(channel)
+	if channelType.Kind() == reflect.Chan {
+		Printfln("Channel Type: %v, Direction: %v", channelType, channelType.ChanDir())
+	}
+}
+
+func sendOverChannel(channel interface{}, data interface{}) {
+	Printfln("\nsendToChannel:")
+	channelVal := reflect.ValueOf(channel)
+	dataVal := reflect.ValueOf(data)
+	if channelVal.Kind() == reflect.Chan && dataVal.Kind() == reflect.Slice && channelVal.Type().Elem() == dataVal.Type().Elem() {
+		for i := 0; i < dataVal.Len(); i++ {
+			val := dataVal.Index(i)
+			channelVal.Send(val)
+		}
+		channelVal.Close()
+	} else {
+		Printfln("Unexpected types: %v , %v ", channelVal.Type(), dataVal.Type())
+	}
+}
+
+func createChannelAndSend(data interface{}) interface{} {
+	Printfln("\ncreateChannelAndSend:")
+	dataVal := reflect.ValueOf(data)
+	channelType := reflect.ChanOf(reflect.BothDir, dataVal.Type().Elem())
+	channel := reflect.MakeChan(channelType, 1)
+	go func() {
+		if dataVal.Kind() == reflect.Slice {
+			for i := 0; i < dataVal.Len(); i++ {
+				channel.Send(dataVal.Index(i))
+			}
+		} else {
+			Printfln("data not Slice types:  %v ", dataVal.Type())
+		}
+		channel.Close()
+	}()
+	return channel.Interface()
+}
+
+func DisplayChan(channel chan string) {
+	for {
+		if val, open := <-channel; open {
+			Printfln("Received value: %v", val)
+		} else {
+			Printfln("Channel closed")
+			break
+		}
+	}
+}
+
+func readChannels(channels ...interface{}) {
+	channelsVal := reflect.ValueOf(channels)
+	cases := []reflect.SelectCase{}
+	for i := 0; i < channelsVal.Len(); i++ {
+		cases = append(cases, reflect.SelectCase{
+			Dir:  reflect.SelectRecv,
+			Chan: channelsVal.Index(i).Elem(),
+		})
+	}
+	for {
+		caseIndex, val, ok := reflect.Select(cases)
+		if ok {
+			Printfln("Index %v Value Read: %v Type: %v from channel %v", caseIndex, val, val.Type())
+		} else {
+			if len(cases) == 1 {
+				Printfln("All Channel closed")
+				return
+			}
+			// 将当前通道删除,从而避免下次Select的时候重复处理
+			cases = append(cases[:caseIndex], cases[caseIndex+1:]...)
+		}
+	}
+}
+
+func testChannelRead() {
+	Printfln("\ntestChannelRead:")
+	var c chan<- string
+	inspectChannel(c)
+
+	values := []string{"Alice", "Bob", "Charlie", "Dora"}
+	channel := make(chan string)
+	go sendOverChannel(channel, values)
+	DisplayChan(channel)
+
+	channel = createChannelAndSend(values).(chan string)
+	DisplayChan(channel)
+}
+
+func testChannelRead1() {
+	Printfln("\ntestChannelRead1:")
+
+	values := []string{"Alice", "Bob", "Charlie", "Dora"}
+	channel := createChannelAndSend(values).(chan string)
+
+	cities := []string{"London", "Rome", "Paris"}
+	cityChannel := createChannelAndSend(cities).(chan string)
+
+	prices := []float64{279, 48.95, 19.50}
+	priceChannel := createChannelAndSend(prices).(chan float64)
+
+	readChannels(channel, cityChannel, priceChannel)
+
+}
+
+func main32() {
+	Printfln("\nmain32:")
+
+	testChannelRead()
+
+	testChannelRead1()
+}