factory method

channel/buffed/main.go

@@ -11,6 +11,7 @@ func main() {
 	ch := make(chan int, 2)
 
 	go func(ch chan int) {
+
 		for i := 1; i <= 5; i++ {
 			ch <- i
 			fmt.Println("Func goroutine sends data: ", i)

creational/factorymethod/main.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/davecgh/go-spew/spew"
+)
+
+type PaymentMethod interface {
+	Pay(amount float32) string
+}
+
+const (
+	Cash      = 1
+	DebitCard = 2
+)
+
+type CashPM struct{}
+
+func (c *CashPM) Pay(amount float32) string {
+	return fmt.Sprintf("%v paid using cash\n", amount)
+}
+
+type DebitCardPM struct{}
+
+func (c *DebitCardPM) Pay(amount float32) string {
+	return fmt.Sprintf("%v paid using DebitCard\n", amount)
+}
+
+func GetPaymentMethod(m int) (PaymentMethod, error) {
+	switch m {
+	case Cash:
+		return new(CashPM), nil
+	case DebitCard:
+		return new(DebitCardPM), nil
+	default:
+		return nil, errors.New(fmt.Sprintf("Payment method %d was not recognized"))
+	}
+}
+
+func main() {
+	paymentMethod, err := GetPaymentMethod(Cash)
+	if err != nil {
+		fmt.Sprintf("Error %s", err.Error())
+	}
+	spew.Dump(paymentMethod.Pay(32))
+}