Implemented the design-pattern exercise

go/exercises/design_pattern/design_pattern.go

@@ -0,0 +1,82 @@
+package main
+
+import "fmt"
+
+//Implementation of the factory design pattern:
+
+type Transporter interface {
+	transport()
+	load()
+	unload()
+}
+
+type Truck struct {
+	name string
+}
+
+type Ship struct {
+	name string
+}
+
+var _ Transporter = Truck{} //Ensures that the "Transporter" Interface is implemented.
+var _ Transporter = Ship{}  //Ensures that the "Transporter" Interface is implemented.
+
+func (t Truck) transport() {
+	fmt.Println("Transporting via ", t.name)
+}
+
+func (t Truck) load() {
+	fmt.Println("Loading cago on ", t.name)
+}
+
+func (t Truck) unload() {
+	fmt.Println("Unloading cargo from ", t.name)
+}
+
+func (t Ship) transport() {
+	fmt.Println("Transporting via ", t.name)
+}
+
+func (t Ship) load() {
+	fmt.Println("Loading cago on ", t.name)
+}
+
+func (t Ship) unload() {
+	fmt.Println("Unloading cargo from ", t.name)
+}
+
+type TransportFactory interface {
+	create(string) Transporter
+}
+
+type TruckFactory struct{}
+
+type ShipFactory struct{}
+
+func (TruckFactory) create(name string) Transporter {
+	return Truck{name}
+}
+
+func (ShipFactory) create(name string) Transporter {
+	return Ship{name}
+}
+
+var _ TransportFactory = TruckFactory{} //Ensures that the "TransportFactory" Interface is implemented.
+var _ TransportFactory = ShipFactory{}  //Ensures that the "TransportFactory" Interface is implemented.
+
+func main() {
+
+	var shipFactory TransportFactory = ShipFactory{}
+	var truckFactory TransportFactory = TruckFactory{}
+
+	ship1 := shipFactory.create("evergreen")
+	ship1.load()
+	ship1.transport()
+	ship1.unload()
+
+	truck1 := truckFactory.create("scania")
+	truck1.load()
+	truck1.transport()
+	truck1.unload()
+
+}